Sassanids from beginning to end – Skills (History of Sassanid rule)

at the end of life Parthian dynasty The continuation of the conflict between the elders of the country, due to the dissatisfaction of two groups of them Parthian government became . The first group were the followers of the religious freedom policy Parthian kings To Zoroastrianism They felt worried .

On the one hand, freedom of action of Christian and Buddhist religions is a threat against Zoroastrian religion who was perceived and on the other hand the lack of unity of power Zoroastrians would reduce . The lack of unity among religious leaders was originally caused by the failure of the Parthian government to adopt a unified and centralized political and religious policy in the country..

The second group was the horsemen, the main core of the army . The horsemen, whose main way of economic progress was in the conquest of new lands, the defensive policy of the Parthians against the Romans, and especially the defeats they suffered at the end of the campaign, were considered the reason for their unworthiness. They were to fight the Romans and gain conquests .

Sasan family in Pars – The history of the formation of the Sasanian government

The main force of opponents of the Parthian government was located in Pars . As the origin of the old Achaemenid state, the state of Pars was still very important . In addition, a number of nobles of the country, who were from old families, lived there and had land, cavalry or religious jobs. . Among the old dynasties of Pars, there was the Sasanian dynasty, which was related to the Achaemenians .

The great Sasan of this family was in charge of Anahita temple in the city of Ashtrak . The city of Astakhar was located near Persepolis, the capital of the Achaemenid Empire, and its temple was considered one of the most important temples . Sasan was not satisfied with the Parthians, like many Persian elders, and in general, at the time of the establishment of the Parthian dynasty, the state of Pars had resisted it and maintained its internal independence. .

Because Sasan married the daughter of the ruler of Pars, in addition to his religious position, he also got a political position . Especially since a son was born from this marriage to the government ( The kingdom of Persia arrived . This son's name was Babak, and during his rule, the prestige and influence of the Sasanian family increased more and more .

This caused concern to Ordavan, the last Parthian king, because he was aware of the enmity of the Sasan family with the Parthian government and he knew how much Ardeshir son of Babak was working against the Parthian government. For this reason, he asked Babak to appoint Ardeshir as the ruler after him. Do not appoint Pars .

During his father's time, Ardeshir was in charge of the cavalry, thus he became more firm in his enmity and opposition to the Parthians and tried to bring the disaffected elders and priests with him in order to overthrow the Parthians. .

Ardeshir and the establishment of the Sassanid government

By resorting to military force, Ardeshir took over the government of Pars and thus revealed his revolt against the Parthian king's army. . Ordavan tried to crush him with the help of his allied elders, but Ardashir's initiative brought him a great victory. . As a result, Ordvan rushed to confront Ardeshir, but he was also defeated and killed on the battlefield . With the murder of Ordavan, the Parthian government ended and the Sassanid government was established . In this way, Ardeshir came from the kingdom of Pars to the kingdom of Iran, and with the help of his allied elders, he broke the remnants of the power of the allied Parthian families. . In his conquests inside Iran, Ardeshir removed the power of the Al-Tawaif kings and elevated those Al-Tawaif kings who accompanied him to high positions in the court of your central government. . As a result, along with the dismantling of the monarchy system, a centralized government was created based on political unity . This transformation required the creation of suitable administrative organizations for the administration of the country . For this purpose, a wide administrative system was created, the highest authority of which was the grand minister or the prime minister . The Grand Vizier was one of the nobles of the Sassanid family and under him were other state, military, financial, and judicial officials. .

Creating religious unity in the Sassanid government

Ardeshir's military operations against the Parthians and his political efforts to gain the support of the nobles were accompanied by the participation of Mobdan. . Like his grandfather Sasan, Ardeshir also showed interest in reforming religious affairs, and the priests were with him in this matter . Ardeshir believed that the reason for the religious division of Zoroastrians is the multiplicity of the kingdoms of the clans because every kingdom in every state has a fire temple whose religious affairs are independent from other fire temples. . Therefore, the establishment of political centrality and removal of local kings will pave the way for unity and concentration in religious affairs . Therefore, the position of Mobad Mobadan in the Sassanid government became very important . Mobad Mobadan was the head of all Mobadan and the management of fire temples . Thus, Ardeshir I, who reigned from 226 to 241 AD, took several important actions with the establishment of the Sassanid government. :

Important actions of Ardeshir I Sassanid

۱- Dividing people into different classes and determining the minimum livelihood and facilities

2- The creation of a political center and the elimination of tribal rulers during the Parthian period

۳- Revival of the Immortal Corps like the Achaemenids

4- Special attention to public security by agents who

They were sent from the center to different places

5- Creating religious unity

6- Seizing India up to Punjab

The kingdom of Shapur I {240 to 272 AD}

Most of the days of Ardeshir's reign were spent on the internal affairs of the country, and only once did he have the opportunity to demonstrate the ability of the new government in the war against the Romans. . But his son and successor Shapur I spent most of his time on conquests and opening up the country .

Shapur I, the son of Ardeshir Babakan, faced the rebellion of Haran and Armenia at the beginning of his reign. He easily put down the Armenian rebellion, but the people of Haran showed such resistance that it was impossible to suppress it.. In order to commit the betrayal of Prince Haran, Tarvaza opens and Shapur kills everyone, including the prince.

After conquering Haran, he conquered the cities of Kerman, Khuzestan, Oman, Makran, Gharb, Khorasan and Turan.. Shapur's first war with the Romans {From 241 to 244 AD} After his conquests, Shapur became aware of Rome and waged a battle with that state. In the first battle, after taking over Antioch and Nasibin, he was defeated by Gardin and Nasibin was lost to him.. Gerdin was killed by his generals, and after him, Philip the Arab became the king.

He signed a compromise with Iran in which Mesopotamia and Armenia were returned to Iran. The second war of Shapur with the Romans {From 244 to 272 AD} As in his first war, Shapur crossed the Euphrates and occupied the surrounding areas, and when the Roman forces came close to the Sassanid armies, he put them in such trouble that Roman Emperor Valerian and many of his troops were captured. He was one of the prisoners of war to build a bridge. and used Sush Dam. After the Romans defeated the cities of Asia Minor, he completely conquered Cappadocia and was defeated by Palmyra.. He died in 272 AD. Shapur II {From 311 to 379 AD} Shapur was the king before he was born and when he was 16 years old, he took over the country.

Some historians have given him the title of Kabir. If Anushirvan was not in this dynasty, surely he would have been the peak of Sasanian power. Shapur is originally from the power of the courtiers {who had many powers since his childhood} and defended the Arab borders. The occupation of Bahrain happened during his time. Apparently, during the war with the Arabs, Shapur used to pierce their shoulder blades, that's why he was called "Zolaktaf"..

With the death of Constantine and the fall of the Roman and Armenian emperors in 337 and 314 AD, Shapur fought with Rome over Armenia.. Thus, Armenia fell into the hands of Iran again. After this he incited the Arabs and pagans "they were from the country of Armenia" to attack Rome, they were temporarily defeated.. Shapur attacked Rome and besieged Nasibin, but he was unable to overcome them, however, he had defeated the Roman army in the plain and made a friendship treaty with Armenia at this time. {۳۴۱میلادی}. In 342 AD, Shapur attacked Mesopotamia and faced Constantine's army in present-day Sinjar..

In this battle, the Romans were severely defeated and massacred. At the time when he saw the victory over Nusaybin near, the news reached him that the small Kushans and Hayatle Khion attacked the eastern borders. He fought with them for 7 years until he was able to defeat them. {۳۵۰-۳۵۷}

But Shapur made a peace treaty with the Romans before the war with the small Kushans and Hayatele, which is as follows:

Description of Iran peace agreement (Sassanids and Rome – 356 AD )

Shapur first wrote to him like this: “Shapur, the king of kings, the brother of Mehr and Mah and the counterpart of the stars, greets his brother Constantius and is happy that the emperor has returned to the right path due to his experience.. My ancestors had extended their territory to the Strymon river near Macedonia. I was superior to all my ancestors in glory, majesty and virtue, and I consider it my duty to defend Armenia and Mesopotamia, which were taken away from my ancestors by trickery.. Give me back these small lands that only cause disunity and bloodshed; And I tell you that if my ambassador returns without a positive answer, after the winter is over I will come to your war with all my force..

” The Roman emperor "Constantius, the opener of the seas and lands and the Lord of eternal glory" writes in response to "his brother Shapur": "If the Romans sometimes prioritize defense over attack, it is not out of fear, but tolerance. Although the Romans sometimes did not win, the final result of the war was never against them.

The Roman emperor could not prevent the war with this frivolous answer, and Shapur II conquered all the lands mentioned in the letter and defeated Rome with difficulty, and the Roman king was punished for his foolish answer.. Later, Shapur invaded Armenia and occupied many lands. But in the end it failed. He enacted a law to ban Christianity in Iran. If we ignore some of his angers, he was a powerful and strong-willed king. He passed away in 379 AD.

Ardeshir II Sassanid kingdom – 379 to 382 AD

After the death of Shapur I, his brother-in-law became king. He was a weak-minded, weak-willed person, but at the same time, he was very obedient, kind-hearted, and pure-intentioned.. On the coins left by him, the word benefactor (Garb Kartar) It can be seen. During his reign, the Christians of the land he previously ruled {Adiaben} It bothered him a lot. According to some historians, he was the elder brother of Shapur Kabir. After 4 years of useless reign, Ardeshir II was removed from his position by the elders of the country

The emergence of Mani religion in Sassanid rule

Mani gave the appropriate answer to the question of the difference and cultural diversity of Shapur I's territory . Mani was one of the scholars of the early Sassanid era, but his birth and upbringing belonged to the late Parthian government . At that time, the presence of several religions and religions in the Parthian territory and their policy of religious freedom had provided a good opportunity for the followers of different religions and religions to get to know each other. . In such an environment, Mani got acquainted with many sciences and religions and by traveling to different areas, he increased his knowledge and became famous. . At the end of Shapur's reign, Mani made his way to his court and presented his religion, which was a mixture of Christianity, Zoroastrianism, Buddhism and popular philosophical thoughts at that time. . This religion actually meant to match the religion of Iranians with other popular beliefs and as a ritual that tried to create a common religion by combining all beliefs. . Shapur considered Mani's religion to be a suitable solution for the unity of his territory as much as possible and supported him . But Mobdan's opposition to Mani, who considered his beliefs to be deviation and apostasy, prompted Shapur to stop supporting Mani. . It didn't take long for Shapur to pass away and Mani had no choice but to leave the country . Although this is less than the position of his fans in Iran, but outside of Iran, especially in Central Asia, Mani gained many followers. .

The officialization of Zoroastrian religion in the Sassanid government

Mani's actions and thoughts made Mobdan to strive more . Among them, one of them named Kartir tried to strengthen the position of Zoroastrianism . Sassanid kings after Shapur I were also weak people for a long time . As a result, Cartier played an important role in the administration of the country's affairs, and following his efforts, Zoroastrian religion became the official religion . As a result of the actions of Cartier and a number of other priests, the affairs of fire temples became more regular and their jobs and responsibilities became more precise. . At this time, Mobad Mobadan's power reached such a level that he was directly involved in the selection of the crown prince . During the coronation, Mobad Mobadan would put a crown on the head of the new king .

With the officialization of the Zoroastrian religion, from now on, all laws, trials, personal circumstances, and government actions must be in accordance with the official religion. . Followers of other religions were restricted and required to obey the laws and orders of the central government in many matters . Among other actions that took place along with the officialization of the Zoroastrian religion . It was an attempt to collect and organize the Avesta.

Shapur II Sasanian kingdom

After Shapur I, seven people sat on the throne . In their time, due to the strength of the elders and the conflict between them, the situation became troubled . Foreign invaders also attacked the borders . Among them, tribes of Arabs rushed to the borders of Iran in Mesopotamia, started looting villages and cities and killing people. . Therefore, the first action of Shapur II was to suppress the invading Arabs . After getting rid of the primitive Arabs, the old differences between Iran and Rome once again led the two countries to war, but the arrival of the news of the invasion of desert tribes to the north of Khorasan prompted Shapur II to rush to confront them first. . Since the attack of the wandering and primitive tribes of the desert was accompanied by the brutal destruction of settlements, the looting of farms and the killing of border dwellers, in such cases, the residents of the borders were very afraid and many problems occurred. . For this reason, it was very necessary to repel the danger of these invaders . The campaign to North Khorasan was successful and allowed the Sassanid government to resume the unfinished war with the Romans. .

The war between the Sassanid government and the Romans

Free from the war with the invading tribes, made it possible to gather a large force to confront the Romans . Between the rule of Shapur I and Shapur II, the Romans had achieved great political and military superiority . At this time, the Roman Empire was dividing into two parts, the Eastern Roman and the Western Roman . Eastern Rome, which received an important part of the Roman troops and before the arrival of Shapur II in 310 AD, captured large parts of the border areas of Iran. . The wars of Shapur II with the Romans started over the issue of Armenia, a huge army of Romans who rushed to confront the Iranians with the intention of capturing Tesifon, the capital of Iran, located on the banks of the Tigris River, advanced with a ship and quickly in the Jaleh River They reached the walls of Tisphon, but when they faced Iranian resistance, they realized that they would not win . This was while the Iranian cavalry had blocked the way back and the Romans could not use the ship due to the opposite flow of water. . Therefore, they left for Rome on foot, where they were chased by Iranian horsemen and the Roman army was practically destroyed .

After this attack, the advance of the Iranians to the west began and they were able to defeat the Romans. After this defeat, the Romans agreed to accept all the conditions of Iran and pledged not to interfere in the affairs of Armenia. .

***

Kingdom of Bahram V

In the fifth century after Shapur II, ten Sassanid kings have ruled, the most famous of which is Bahram V known as Bahram Gur. . In this century, one of the important issues of Sasanian society was the issue of Christians .

In the fourth century AD, Christianity became the official religion of Rome . The support of the Roman government to the Christian Tebra of the Sassanid government created new problems . Because a number of residents of the western borders of Iran and especially in Armenia had become Christians . Christians who, in terms of their religious affairs, were directed towards their religious center of the Eastern Roman Empire . They were constantly being pressured by the Sassanid government for accompanying and cooperating with the Romans . In addition, because every day a number of Iranians became Christians . This was expensive for the Sassanid government and the Mobdans, this kind of affairs made the internal situation of Iran chaotic and gave an opportunity to the Mobdans and elders who wanted to exploit the oppression of Christians for their own benefit. . As many times, there was a dispute between them and the Sassanid kings regarding the fact that they did not treat the Christians well with the priests, because the kings wanted to treat the Christians well. .

Wars of Bahram V

During the reign of Bahram V, the issue of Christians caused a renewed conflict between Iran and Rome . As a result, the parties prepared for war again . But the invasion of the Hayatele desert tribe to the north of Khorasan made it more necessary for Bahram V to deal with it . Bahram's plan was to surprise them and it happened . As a result, they were crushed and fled to the other side of the Jihun River . After the defeat of the enemy, the war between Iran and Rome started, and although it continued for years, none of the sides were definitively victorious. . As a result, they agreed to peace . In this peace, it was decided that Christians in Iran and Zoroastrians in Rome would have freedom . But due to Mobdan's opposition, this appointment was not carried out .

The kingdom of Qabad and the problem of Mazdakians

When the Sassanid king Qubad came to the throne in 487 AD, the Sassanid government had many problems .

The problems of the Sassanid government were briefly: :

1- Foreign wars of the Sassanid government were repeated every few years .

2- The differences between the king and the elders were among the issues that

The Sassanid government witnessed it early on when each new king came to power .

elders ( Reverends, army commanders and... ) who wanted to increase their power and always wanted to bring the king under their influence .

3- The struggle of elders with each other to get more points and high officials was also one of the struggles that never ended. .

4- The class system of Sassanid society .

After the reign of Bahram Gur

After Bahram Ghor, the Hayatela once again resumed their attacks and looted the border areas . Pirouz was killed by Sassanid kings who had gone against them . As a result of these events, chaos and many problems arose . And there was a great conflict over the appointment of the crown prince .

In such a situation, one of the elders, whose name was Mazdak, and who favored the crown prince Kaus, the son of Qobad, tried to attract Qobad's attention. . The reason why Qobad paid attention to Mazdak was the fans he got from him . In the conditions of drought and the general problem of food, Mazdak had demanded the distribution of wheat from government warehouses among the people . Also, he did not agree with the encroachment of the military on the property and property of Spoorhan in those circumstances . When Qabad saw people's attention to Mazdak, he brought him close to him and took measures with his advice . Mazdak and his supporters also supported Qabad against the elders who opposed him . So Qabad got the opportunity and killed the opposing elders.

The actions of Qobad and Mazdak could not quickly suppress all the opposition elders, and as a result, some of them had the opportunity to express their opposition and take action. . In this way, Mubadan, who was one of Mazdak's opponents, and Anushirvan, another son of Qabad, accompanied them. . By making Anoushirvan the crown prince against Kaus, they also gained the collective support of the courtiers . Because this group increased their opposition to Qabad, and he, who saw the foundation of his family's monarchy in danger, joined Anushirvan and turned away from the Mazdakians. . After that, Mazdak and his followers were killed . The story of the Mazdakians apparently ended, and at the end of this story, Anushirvan became the king of Iran .

Kingdom of Anushirvan Adel

In the first years of his reign, Anushirvan suppressed the remnants of Mazdak and punished those nobles and soldiers who had accompanied Mazdak. . Anushirvan made reforms during his reign, among other things, he changed the way the military was organized, so that it would be better monitored and more active to deal with foreign invasions. . Also, he changed the way of paying the salaries of the soldiers and thus calmed them down . Another measure of Anushirvan was to change the method of collecting taxes and handling complaints, as he sent agents to the provinces to investigate the actions of governors and investigate people's complaints. . These measures relied more on Anoushirvan's individual abilities and made the situation orderly and calm . In fact, Anushirvan made the Sasanian government strong again, and for that reason, he is considered one of the most famous kings of that dynasty. . At the beginning of Anushirvan's reign, due to the disorder in his internal situation, he tried to find friendship with the Roman government. . The Roman emperor Justinian also accepted his peace proposal as he was planning to launch campaigns in Europe. . After the peace and reconciliation between the two governments, Justine Nin succeeded in many conquests in the northern regions. Anoushirvan was worried about his powerful . By this time, he had succeeded in calming down the internal situation . As a result, in search of an opportunity, following the difference between the two governments, Hira and Ghassan were found . Hirah was an Arab state that was located on the borders of Iran and was subordinate to the Sassanid government . Ghassan was also an Arab state that was located in Syria and was considered a subordinate state of the Roman state . The differences between Hayrah and Ghassan and the intervention of Justinian provided the right opportunity to declare war on Rome . Therefore, he moved towards Syria with a large army and by conquering that land, he paid heavy compensation to the Romans . Then they defeated the Romans in another war and accepted their conditions . Anoushirvan was also able to defeat and expel the Abyssinians from Yemen in subsequent wars, making the country of Yemen subordinate to the Iranian government. . Also, by uniting with the Turks in Central Asia, the Iranian troops were able to inflict a severe defeat on the tribes of Hayatele .

Kingdom of Khosrow Parviz

After Anushirvan, his son Hormuz IV came to the throne . During his time, the elders of the country gained a lot of power, and most of Hormuz's time was spent limiting their actions . Among these elders is a person named Bahram Chubin, who was one of the army commanders . At that time, the Turks attacked North Khorasan, Bahram went to war against them and was able to win a great victory . Bahram's great fame caused Hormoz to worry and he did not receive Bahram well on his return. . During the rebellion, one of the sons of Hormuz, named Khosrow Parvez, escaped from Iran and became a refugee of the Roman government, the Roman government provided Khosrow Parvez with a huge army by taking many privileges. . Khosrow Parvez was able to defeat Bahram Chubin with the help of the Roman troops and become the king of Iran. After reaching the throne, Khosrow Parvez organized a very luxurious court for himself. . In his court, the Christians, who were under pressure until then, gained a lot of influence . Because one of Khosrow's wives named Maryam was the daughter of the Roman emperor and another one of his wives named Shirin was also a Christian . This matter was not approved by Mobdan, but Khosrow's violence did not allow anyone to disagree with him .

Not long after the reign of Khosrow Parvez, his father-in-law, Caesar of Rome, was killed during a rebellion . Khosrow Parviz, who was looking for an opportunity to open the country, used the blood lust of the Roman emperor as an excuse and provided a huge force for the war. . Khosroparviz's armies entered the Roman territory from two sides . A part of the army went to Syria and after capturing Syria, Palestine and Lebanon, they reached the Mediterranean Sea.

The other part of the army entered Asia Minor and advanced towards Constantinople, the capital of Rome . The conquests that the Iranian army made until this time were due to the efforts and sacrifices of two generals known as Shaherbraz and Shahin. . At the last stage of his advance, Shaherbraz also conquered Egypt and Shahin reached the gates of Constantinople . By this time, more than ten years had passed since the start of the Persian-Roman wars .

Heraclius offered peace to Khosrow Parviz. The Iranian generals also thought of ending the advance . Because the Iranian troops had reached the shores of the Mediterranean and Black seas, and the continuation of the battle was only possible with the navy . While Iranians had no navy and Rome had a powerful navy . But Khosrow Parviz, who had become very proud and was eager to get many other spoils, refused to make peace. . As a result, while the Iranian troops were tired, the Romans entered the war with all their might to save themselves .

Heraclius' plan was to use the navy to land the force in the closest position to Iran . For this reason, while the Iranian troops had advanced deep into Roman territory, he disembarked from the ship with his troops in Georgia and quickly attacked Azariaijan. . This action of his was considered an attack on the back of the Iranian front, and before the different Iranian armies joined together, he surprised them and broke them. . While destroying cities and villages, Heraclius advanced from Azerbaijan to Tisophon . Khosrow Parvez was in charge of the Iranian army to fight him .

Because Shahin had died at this time and Shahrbraz had maintained all his positions in Syria and Egypt with his strength. . But Khosrow escaped from Heraclius and defeated the Iranians . One of the reasons for this defeat was Khosrow's mistreatment of generals and soldiers, which made them very angry .

After the defeat of Rome, the soldiers and generals revolted, arrested Khosrow Parvez and put him in prison. . Khosrow Parviz's wars with the Romans lasted nearly 25 years, and the casualties and injuries that came to Iran from these wars are considered one of the important factors in the fall of the Sassanids. .

The fall of the Sassanid government

The disgruntled elders killed Khosrow Parvez in prison and put his son Shiravieh on the throne in 629 AD. . But he was also killed in the same year . Within a year, three people sat on the throne, but were immediately deposed or killed . At that time, the division and struggle for power became so much that it is said that within four years, twelve people reached the throne, but they were not successful in their work. . At this time, due to the weakness of the kingdom and the inability to repel the attacks of the Romans and immigrant tribes, the country's situation had become very chaotic, and Yazd Gard III, the last Sassanid king, could not improve this situation. .

The invasion of the Arabs to Iran during the Sassanid regime

Around the year 633 AD equal to 12 AH, Muslims reached the shrines of Iran . Before that, Muhammad Ibn Abdullah had invited him to Islam through a letter to Khosrow Parvez .

After the death of Muhammad and during the caliphate of Abu Bakr, Khaledin Walid reached the borders of Iran in Mesopotamia with Arab troops. . On the borders of Iran, one of the chiefs of the Arab tribes adjacent to the borders of Iran, named Mushani bin Haritha, guided him. . Before Khosrow Parvez, the duty of defending Iran's borders against the Bedouins was with the Hirah government . But when Khosrow Parviz removed the government of Hirah, the Iranian border guards were responsible for confronting the Bedouins . Khaledin Walid defeated the border guards in the attack on Iran .

In the year 14 AH equal to 636 AD, the Arab armies won against the Iranian army under the command of Rostam Farrokhzad in the battle of Qadsiyah. Following this defeat, the city of Madain, the capital of the Sassanids, fell. . Yazgerd III retreated to the center of Iran . In the year 21 Hijri, near Nahavand, the Sassanid troops lined up against the Arabs . In this war, the Sassanid army was defeated, Yazgerd III fled to the north of Khorasan, the Arabs entered Iran, and one after another the cities and settlements were destroyed and fell by the Arabs. .

In the year 31 Hijri, Yazgerd III was killed in the north of Khorasan by a miller who coveted his silk clothes and woven gold, and thus in the year 31 Hijri equal to 652 AD, the glorious reign of the Sassanid dynasty ended. .

Arts and techniques of the Sassanid era

One of the most important works left from the Sassanid era is the large buildings made of stone and plaster . These buildings, which include fire temple, palace and castle, can be seen everywhere in Iran . During the Sassanid era, many cities were built, all of which had towers and ramparts and other defense facilities . Like Bishapur and Firozabad(Pirouzabad) In Fars province, Gandishapur, Tisfon and the like . In these cities, there were fire temples, palaces and castles, whose traces are still there . Madain Palace near Baghdad, Dokhtar Castle near Firozabad and Firezabad Fire Temple are among them . One of the important buildings of the Sassanid period was Gandishapur, which was a scientific and educational center and, as it were, the first university in the world .