Not long after Michael became Prince of Wallachia, he turned against the Ottoman Empire. The next year he joined the
Christian alliance of
European powers formed by
Pope Clement VIII against the Turks, and signed treaties with his neighbours:
Sigismund Báthory of Transylvania,
Aaron the Tyrant of
Moldavia and the Holy Roman Emperor,
Rudolf II (see
Holy League of Pope Clement VIII). He started a campaign against the Turks in the autumn of 1594, conquering several citadels near the
Danube, including
Giurgiu,
Brăila,
Hârșova, and
Silistra, while his Moldavian allies defeated the
Turks in
Iași and other parts of Moldavia. Michael continued his attacks deep within the Ottoman Empire, taking the forts of
Nicopolis, Ribnic, and
Chilia with his soldiers raiding as far as
Razgrad, which led to rumors that his army reached
Adrianople. In 1595,
Sigismund Báthory staged an elaborate plot and had Aaron the Tyrant, voivode of Moldavia, removed from power.
István Jósika (Báthory's chancellor and an ethnic Romanian) masterminded the operation.
Ștefan Răzvan arrested Aron on charges of treason on the night of 24 April (5 May) and sent him to the Transylvanian capital at Gyulafehérvár with his family and treasure. Aron would die poisoned by the end of May in the castle of
Vinc. Sigismund was forced to justify his actions before the European powers, since Aron had played an active role in the anti-Ottoman coalition. Later on, in the same city of Gyulafehérvár (Alba Iulia, in Romania of today), Wallachian boyars signed a treaty with Sigismund on Michael's behalf. From the point of view of Wallachian internal politics, the "Treaty of Gyulafehérvár" codified what could be called a
boyar regime, reinforcing the already important political power of the noble elite. According to the treaty, a council of 12 great boyars was to take part alongside the
voivode in the executive rule of the country. Boyars could no longer be executed without the knowledge and approval of the Transylvanian Prince and, if convicted for treason, their fortunes could no longer be confiscated. Apparently Michael was displeased with the final form of the treaty negotiated by his envoys, but was forced to comply. Prince Michael said in a conversation with the
Polish envoy Lubieniecki:
... they did not proceed as stated in their instructions but as their own good required and obtained privileges for themselves. He would try to avoid the obligations imposed on him for the rest of his reign. During his reign, Michael relied heavily on the loyalty and support of a group of Oltenian lords, the most important of whom were Buzescu Brothers (Romanian:
Frații Buzești) and his own relatives on his mother's side, the Cantacuzinos. He consequently protected their interests throughout his reign; for example, he passed a law binding serfs to lands owned by aristocrats. From the standpoint of religious jurisdiction, the Treaty of Gyulafehérvár had another important consequence: it placed all the
Eastern Orthodox bishops in Transylvania under the jurisdiction of the Metropolitan Seat of
Târgoviște. During late 1596, Michael was faced with an unexpected attack from the
Tatars, who had destroyed the towns of Bucharest and
Buzău. By the time Michael gathered his army to counterattack, the Tatars had speedily retreated and so no battle was fought. Michael was determined to continue the war against the Ottomans, but he was prevented because he lacked support from Sigismund Báthory and Rudolf II. On 7 January 1597
Hasan Pasha declared the independence of Wallachia under Michael's rule, but Michael knew that this was only an attempt to divert him from preparing for another future attack. Michael again requested Rudolf II's support and Rudolf finally agreed to send financial assistance to the Wallachian ruler. On 9 June 1598 a formal treaty was reached between Michael and Rudolf II. According to the treaty, the Austrian ruler would give Wallachia sufficient money to maintain a 5,000-man army, as well as armaments and supplies. Shortly after the treaty was signed, the war with the Ottomans resumed and Michael besieged
Nicopolis on 10 September 1598 and took control of
Vidin. The war with the Ottomans continued until 26 June 1599, when Michael, lacking the resources and support to continue prosecuting the war, signed a peace treaty. == Transylvania ==