Michael the Brave in Gyulafehérvár on 20May 1595. According to the treaty, Michael was forbidden to enter into an alliance with foreign powers without Sigismund's approval. The voivode's right to sentence his boyars to death was also limited. The Diet of Transylvanian was authorized to impose taxes in Wallachia with a council of twelve boyars. After Aaron the Tyrant refused to sign a similar treaty, Sigismund invaded Moldavia and captured him in Iași. He made Ștefan Răzvan the new voivode on 3June, forcing him to swear fealty to him. Thereafter, Sigismund styled himself "By the Grace of God, Prince of Transylvania, Wallachia and Moldavia, Prince of the Holy Roman Empire, Count of the Székelys and Lord of Parts of the Kingdom of Hungary". Sigismund married Maria Christina of Habsburg, a niece of RudolphII, on 6August. However, the marriage was never consummated. Sigismund accused (who was the mother of his executed cousin, Balthasar Báthory) of witchcraft, causing his impotence. Historian László Nagy notes that Sigismund's contemporaries made no reference to his relationship with women, showing that Sigismund was homosexual. György Borbély, Ban of Karánsebes, captured Lippa (now Lipova in Romania) and other Ottoman fortresses along the Maros River before the end of August. Koca Sinan Pasha broke into Wallachia, forcing Michael the Brave to retreat towards Transylvania. Michael routed the invaders in the Battle of Călugăreni, but he could not prevent them from seizing Târgoviște and Bucharest. He withdrew to Stoenești to await the arrival of the Transylvanian and Moldavian troops. Since the Ottoman army outnumbered the forces at Sigismund's disposal, he proposed the Székely commoners (who had been reduced to serfdom in the 1560s) to restore their freedom if they joined his campaign against the Ottomans. The Székelys accepted his offer, enabling Sigismund to launch a counter-invasion in Wallachia in early October. The united forces of Transylvania, Wallachia, and Moldavia defeated the retreating Ottoman army in the Battle of Giurgiu on 25October. Although the victory was not decisive, the battle enabled the two voivodes to maintain their alliance with the Holy League. Ignoring the Székely warriors' preeminent role during the war, the Diet of Transylvania refused to restore their freedom on 15December. Sigismund left for Prague to start negotiations with RudolphII in early January 1596, tasking his wife and Stephen Bocskai with the government. The Székelys tried to secure their freedom, but Bocskai repressed their movement with extraordinary cruelty during