carrying out an armed intervention in Transylvania – supporting the pro-Turkish John Zápolya). Conflicts between boyar families became stringent after the rule of Pătrașcu the Good, and boyar ascendancy over rulers was obvious under Petru the Younger (1559–1568; a reign dominated by Doamna Chiajna and marked by huge increases in taxes), Mihnea Turcitul, and Petru Cercel. The Ottoman Empire increasingly relied on Wallachia and Moldavia for the supply and maintenance of its military forces; the local army, however, soon disappeared due to the increased costs and the much more obvious efficiency of mercenary troops. 17th century Initially profiting from Ottoman support, Michael the Brave ascended to the throne in 1593, and attacked the troops of Murad III north and south of the Danube in an alliance with Transylvania's Sigismund Báthory and Moldavia's Aron Vodă (see Battle of Călugăreni). He soon placed himself under the suzerainty of Rudolf II, the Holy Roman Emperor, and, in 1599–1600, intervened in Transylvania against Poland's king Sigismund III Vasa, placing the region under his authority; his brief rule also extended to Moldavia later in the following year. For a brief period, Michael the Brave ruled (in a personal, but not formal, union) most of the territories where Romanians lived, rebuilding the base of the ancient Kingdom of Dacia. The rule of Michael the Brave, with its break with Ottoman rule, tense relations with other European powers and the leadership of the three states, was considered in later periods as the precursor of a modern Romania, a thesis which was argued with noted intensity by Nicolae Bălcescu. Following Michael's downfall, Wallachia was occupied by the Polish–Moldavian army of Simion Movilă (see Moldavian Magnate Wars), who held the region until 1602, and was subject to Nogai attacks in the same year. The last stage in the Growth of the Ottoman Empire brought increased pressures on Wallachia: political control was accompanied by Ottoman economical hegemony, the discarding of the capital in Târgoviște in favour of Bucharest (closer to the Ottoman border, and a rapidly growing trade center), the establishment of serfdom under Michael the Brave as a measure to increase manorial revenues, and the decrease in importance of low-ranking boyars (threatened with extinction, they took part in the seimeni rebellion of 1655). Furthermore, the growing importance of appointment to high office in front of land ownership brought about an influx of Greek and Levantine families, a process already