Maximilian I (17 April 157327 September 1651), occasionally called the Great, a member of the House of Wittelsbach, ruled as Duke of Bavaria from 1597. His reign was marked by the Thirty Years' War during which he obtained the title of a prince-elector of the Holy Roman Empire at the 1623 Diet of Regensburg.
Maximilian was a capable monarch who, by overcoming the feudal rights of the local estates (Landstände), laid the foundations for absolutist rule in Bavaria. A devout Catholic, he was one of the leading proponents of the Counter-Reformation and founder of the Catholic League of Imperial Princes. In the Thirty Years' War, he was able to conquer the Upper Palatinate region, as well as the Electoral Palatinate affiliated with the electoral dignity of his Wittelsbach cousin, the "Winter King" Frederick V. The 1648 Peace of Westphalia affirmed his possession of Upper Palatinate and the hereditary electoral title, though it returned the Electoral Palatinate to Frederick's heir and created an eighth electoral dignity for them.
Background
Maximilian I was born in Munich, the eldest son of William V, Duke of Bavaria and Renata of Lorraine to survive infancy. He was educated by the Jesuits, and following his father's increasing difficulties in ruling the country, began to take part in the government round 1591, but latest 1594. In 1595 he married his cousin, Elisabeth Renata (also known as Elizabeth of Lorraine), daughter of Charles III, Duke of Lorraine, and became Duke of Bavaria upon his father's abdication in 1597.
German politics and the Thirty Years' War
thumb|left|Portrait in armour by [[Nikolaus Prucker]]
Maximilian refrained from any interference in German politics until 1607, when he was entrusted with the duty of executing the imperial ban against the free city of Donauwörth, a Protestant stronghold. In December 1607 his troops occupied the city, and vigorous steps were taken to restore the supremacy of Catholicism. Some Protestant princes, alarmed at this action, formed the Protestant Union to defend their interests, which was answered in 1609 by the establishment of the Catholic League, in the formation of which Maximilian took an important part. Under his leadership an army was set on foot, but his policy was strictly defensive and he refused to allow the League to become a tool in the hands of the House of Habsburg. Dissensions among his colleagues led the duke to resign his office in 1616, but the approach of trouble brought about his return to the League about two years later. He even obtained Dürer's The Four Apostles in the year 1627 due to pressure on the Nuremberg city fathers. Among his court artists were Peter Candid, Friedrich Sustris, Hubert Gerhard, Hans Krumpper, Adrian de Vries and Georg Petel.
The Duke died at Ingolstadt on 27 September 1651. He is buried in St. Michael's Church, Munich. In 1839 a statue was erected to his memory at Munich by King Ludwig I of Bavaria.