||This table may contain original research. (March 2010)|
|This article's factual accuracy is disputed. (March 2010)|
Tapuria (widely known as Tabaristan) was the name of the former historic region in the Southern coasts of Caspian sea roughly in the location of northern and southern slopes of Elburz range in Iran. The region roughly corresponded to the modern Iranian provinces of Mazandaran, Gilan, Golestan, northern Semnan, and a little part of Turkmenistan.
Early history 
The Amardians are believed to have been the earliest inhabitants of the region where modern day Mazanderan and Gilan are located. The establishment of the early great kingdom dates back to about the first millennium BCE when the Hyrcanian Kingdom was founded with Sadracarta (somewhere near modern Sari) as its capital. Its extent was so large that for centuries the Caspian Sea was called the Hyrcanian Ocean. The first known dynasty were the Faratatians, who ruled some centuries before Christ. During the rise of the Parthians, many of the Amerdians were forced into exile to the southern slopes of the Elburz mountains known today as Varamin and Garmsar, and the Tabaris (who were then living somewhere between today's Yaneh Sar to the north and Shahrud to the south) replaced them in the region. During the indigenous Gushnaspian dynasty many of the people adopted Christianity. In 418 CE the Tapurian calendar (similar to the Armenian and Galeshi) was designed and its use implemented. The Gashnaspians ruled the region until 528 CE, when, after a long period of fighting, the Sassanid King Kopad defeated the last Gashnaspian king.
Medieval era 
The Mazandaranis never compromised with Kopad and he soon left the region, but he placed Zarmehr on the throne in 537 CE. As a native of the region, he became popular. Zarmehr traced his genealogy to Kaveh, the legendary smith. During the reign of the Zarmehrians many people gradually converted to Zoroastrianism, and the language of the Mazanderanis was somewhat altered.
When the Sassanid empire fell, Yazdegerd III escaped to Tapuria to make use of the Mazanderani's bravery and resistance to repel the Arabs. By his order, AdarVelash (the last Zarmehrian king) ceded the dominion to Spahbed Gil Jamaspi in 645 CE, while western and Southern Gilan and other parts of Gil's domain merged under the name of Tapuria. He then chose Amol as capital of United Tapuria in 647 CE. The dynasty of Gil was known as Gavbareh in Gilan, and as the Dabuyans in eastern Tapuria.
Tabaristan was one of the last parts of Persia to fall to the Muslim Conquest, maintaining resistance until 761 (cf. Khurshid of Tabaristan). Even afterwards, Tabaristan remained virtually independent of the Caliphate.[page needed]
Farrukhan the Great (the fourth king of the Dabuyans) expanded Tapuria to eastern parts of today's Turkmenistan and repulsed the Turks around 725 CE.
While the Dabuyans were in the Plainy regions, the Sokhrayans governed the mountainous regions. Venday Hormuzd ruled the region for about 50 years until 1034 CE. After 1125 CE, (the year Maziar was assassinated by subterfuge) an increase in conversion to Islam was achieved, not by the Arab Caliphs, but by the Imam's ambassadors.
Mazandaranis and Gilaks were one of the first groups of Iranians to convert directly to Shia Islam.
Modern era 
Tapuria remained independent until 1596, when Shah Abbas I, Mazandarani on his mother's side, incorporated Mazandaran into his Safavid empire, forcing many Armenians, Georgians, Kurds and Qajar Turks to settle in Mazandaran. Pietro Della Valle, who visited a town near Pirouzcow in Mazandaran, noted that Mazandarani women never wore the veil and didn't hesitate to talk to foreigners. He also noted that he had never encountered people with as much civility as the Mazandaranis.
After the Safavid period, the Qajars began to campaign south from Mazandaran with Agha Mohammad Khan who already incorporated Mazandaran into his empire in 1782. On 21 March 1782, Agha Mohammad Shah proclaimed Sari as his imperial capital. Sari was the site of local wars in those years, which led to the transfer of the capital from Sari to Tehran by Fath Ali Shah.
- Seif, Asad. "Islam and poetry in Iran". Iran Chamber Society. Iran Chamber Society. Retrieved 1 March 2011.
- Inostranzev, M. "Tabaristan". IRANIAN INFLUENCE ON MOSLEM LITERATURE, PART I. Project Gutenburg. Retrieved 1 March 2011.
- Goldschmidt, Arthur (2002). A concise history of the Middle East. Boulder, Colorado: Westview Press. p. 84. ISBN 0-8133-3885-9.
- Inostranzev, M. (1918) Iranian Influence on Moslem Literature – Appendix I: Independent Zoroastrian Princes of Tabaristan.
- Khalifa Uthman bin Ghani. Islamic Conquests
- Muhammad B. Al-Hasan B. Isfandiyár (1905) [1216 A.D.]. History of Tabaristán. Leiden, The Netherlands: E.J. Brill.