In 1588 he became a ban of Mehedinţi, then at the end of the 1588 stolnic (commissary) at the court of Mihnea Turcitul, and in 1593 Ban of Craiova during the time Walachia was ruled by Alexandru cel Rău (Alexander the evil). In September 1593 with the help of the Ottomans, he became voivod of Wallachia, starting the effective ruling on October 11.
But it wouldn't take long to fight back against the Turks, the next year he adered to the "Holy League" Christian alliance against the Turks and signed treaties with Sigismund Bathory from Transylvania and Aron Vodă in Moldavia. He started a campaign against the Turks in the autumn of 1594, setting the border on the Danube and conquering several citadels near the Danube, like Giurgiu, Cetatea de Floci, Hārşova and Silistra.
The fights against the Turks continued in 1596, when Michael the Brave did several incursions South of Danube, Vidin, Plevna, Nicopole, Turnu and Babadag.
On October 18, 1599, Michael the Brave obtained an important victory at Selimbar against the cardinal Andrei Bathory. Michael the Brave entered stately Alba Iulia with an impressive pomp, receiving the keys of the fortress from the bishop Napragy.
Next year, on May 8, the Romanian army under the command of Michael the Brave, defeated the armies of Ieremia Movilă and the Polish ones in Bacău, the Romanian nation was for the first time unified under one ruler, but this union did not last, since in 1601 Michael the Brave was killed in Cāmpia Turzii from the order of Habsburgic army leader Giorgio Basta.