The Sassanid dynasty was founded by Ardashir I when he defeated the last Parthian (Arsacid) king, Artabanus IV, and ended when the last Sassanid Shahanshah (King of Kings), Yazdegerd III (632–651), lost a fourteen-year struggle to drive out the early ArabCaliphate, the first of the Islamic empires.
The Sassanid era is considered to be one of the most important and influential historical periods in Iran. In many ways; the Sassanid period saw the highest achievement of Persian civilization, and was the last great Persian Empire before the Muslim conquest and the adoption of Islam.
Persia influenced Roman civilization considerably during the Sassanids,[4]p109 and the Romans reserved for the Sassanid Persians the status of equals. The Roman Emperor wrote letters to the Persian Shahanshah, which were addressed to "my brother". Their cultural influence extended far beyond the empire's territorial borders by reaching as far as Western Europe,[5]Africa,[6]China and India and played a prominent role in the formation of both European and Asiatic mediaeval art.[7]
This influence carried forward to the early Islamic world. The dynasty's unique aristocratic culture transformed the Islamic conquest of Iran into a Persian renaissance.[5] Much of what later became known as Islamic culture, architecture, writing and other skills were borrowed from the Sassanid Persians and spread throughout the broader Muslim world.
Religion
The Sassanids began making the empire “more Iranian” after the fall of the Parthians. They did this by implementing Zoroastrianism.
Zoroastrianism was the backbone and state religion of the Sassanid Empire. It was one of the first monotheistic religions, meaning that the Sassanids believed in one god. The traditional Zoroastrian scripture, Avesta, was originally orally preserved in Avestan, a now-extinct language. However, the Sassanids were the first people to write the Avesta and instead wrote it in an Aramaic script. In addition, many of the civilians who did not follow the Zoroastrian faith were persecuted by the government.
Decline
In the spring of 632, a grandson of Khosrau I, Yazdegerd III, who had lived in hiding, ascended the throne. The same year, the first raiders from the Arab tribes made their raids into Persian territory. They were united by Islam. Years of warfare had exhausted both the Byzantines and the Persians. Also, the latter were further weakened by economic decline, heavy taxation, religious unrest, rigid social classes, the increasing power of the provincial landholders and a rapid turnover of rulers. Those factors made the Islamic conquest of Persia easier than if it had been attempted earlier.
The Sassanids never mounted a truly effective resistance to the pressure that was applied by the Muslim conquests.
603–628: War with Byzantium. Persia occupies Byzantine Mesopotamia, Syria, Palestine, Egypt and the Transcaucasus, before being driven to withdraw to pre-war frontiers by Byzantine counter-offensive.
642: Final victory of Arabs when Persian army destroyed at Nahavand (Nehavand).
651: Last Sassanid ruler Yazdegerd III murdered at Merv, present-day Turkmenistan, ending the dynasty. His son Firuz and many others went into exile in China.
