 Matthias imprisoned Georg Keglević who was the Commander-in-chief, General, Vice-Ban of Croatia, Slovenia and Dalmatia and since 1602 Baron in Transylvania, but soon left him free again.At that time the Principality of Transylvania was a fully autonomous area of Hungary, but under the nominal suzerainty of the Ottoman Empire, where it was the time of the Sultanate of Women.Matthias's conciliatory policies were opposed by the more intransigent Catholic Habsburgs, particularly Matthias's brother Archduke Maximilian, who hoped to secure the succession for the inflexible Catholic Archduke Ferdinand (later Emperor Ferdinand II).