person or an imaginary figure. The gyulas from the seven chieftains of the Hungarians governed Transylvania in the 10th century. King Stephen I of Hungary asserted his claim to rule all lands dominated by Hungarian lords. He personally led his army against his maternal uncle Gyula III and Transylvania became part of the Kingdom of Hungary in 1002. Place names derived from the Hungarian tribes evidence that major Hungarian groups settled in Transylvania from the 950s. In the 12th and 13th centuries, Southeast and Northeast Transylvania was settled by Saxon colonists. After the Battle of Kosovo and Ottoman arrival at the Hungarian border, thousands of Vlach and Serbian refugees came to Transylvania. Between 1002 and 1526, Transylvania was part of the Kingdom of Hungary, led by a voivode appointed by the King of Hungary. After the Battle of Mohács in 1526, Transylvania became part of the Eastern Hungarian Kingdom. Later, in 1570, the kingdom became the Principality of Transylvania by the Treaty of Speyer, which was ruled primarily by Calvinist Hungarian princes. The Eastern Hungarian king became the first prince of Transylvania, according to the treaty. The Principality of Transylvania continued to be part of the Kingdom of Hungary in the sense of public law, which stressed in a highly significant way that John Sigismund's possessions belonged to the Holy Crown of Hungary and he was not permitted to alienate them. The Habsburgs acquired the territory shortly after the Battle of Vienna in 1683. In 1687, the rulers of Transylvania recognized the suzerainty of the Habsburg emperor Leopold I, and the region was officially attached to the Habsburg Empire. The Habsburgs acknowledged the Principality of Transylvania as one of the Lands of the Crown of Saint Stephen, but the territory of the principality was administratively separated from Habsburg Hungary, and subjected to the direct rule of the emperor's governors. In 1699 the Ottomans legally acknowledged their loss of Transylvania in the Treaty of Karlowitz; however, some anti-Habsburg elements within the principality submitted to the emperor only in the 1711 Peace of Szatmár, when Habsburg control over Principality of Transylvania was consolidated. The Grand Principality of Transylvania was reintroduced 54 years later in 1765. The Hungarian revolution against the Habsburgs started in 1848, and grew into a war for the total independence of the Kingdom of Hungary from the Habsburg dynasty. Julius Jacob von Haynau, the leader of the Austrian army,