William IV was Duke of Bavaria from 1508 to 1550, until 1545 together with his younger brother Louis X, Duke of Bavaria.
Background
He was born in Munich to Albert IV and Kunigunde of Austria, a daughter of Emperor Frederick III. Though his father had determined the everlasting succession of the firstborn prince in 1506, his younger brother Louis refused a spiritual career with the argument that he was born before the edict became valid. With support of his mother and the States-General, Louis forced William to accept him as co-regent in 1516.
Career
William initially sympathized with the Reformation but changed his mind as it grew more popular in Bavaria. In 1522 William issued the first Bavarian religion mandate, banning the promulgation of Martin Luther"s works. Both dukes also suppressed the peasant uprising in South Germany in an alliance with the archbishop of Salzburg in 1525.
The conflict with Habsburg ended in 1534 when both dukes reached an agreement with Ferdinand I in Linz.
William then supported Charles V in his war against the Schmalkaldic League in 1546. William"s chancellor for 35 years was the forceful Leonhard von Eck.
William was a significant collector and commissioner of art Among other works he commissioned an important suite of paintings from various artists, including the Battle of Issus by Albrecht Altdorfer.
This, like most of William"s collection, is now housed in the Alte Pinakothek in Munich.
With his order to expand the Neuveste with the so-called Rundstubenbau and to set up the first Court Garden began the history of the Munich Residence as a representative palace. To the history cycle of the garden pavilion belonged Albrecht Altdorfer"s painting. In 1546 he ordered to upgrade Dachau Palace from a Gothic ruin into a renaissance palace.
In 1523 with the appointment of Ludwig Senfl began the rise of the Bavarian State Orchestra.
On 23 April 1516, before a committee consisting of gentry and knights in Ingolstadt, he issued his famous purity regulation for the brewing of Bavarian Beer, stating that only barley, hops, and water could be used. This regulation remained in force until it was abolished as a binding obligation in 1986 by Paneuropean regulations of the European Union.
He is buried in the Frauenkirche in Munich.