John III, Duke of Bavaria

John III the Pitiless (1374–1425), of the House of Wittelsbach, was first bishop of Liège 1389–1418 and then duke of Bavaria-Straubing and count of Holland and Hainaut 1418–1425.

His elder brother was William II, who succeeded their father as count of Holland, Zeeland and Hainault in 1404.

John ordered the beheading of suspicious burghers and noblemen in Liège, while others were drowned in the Meuse, from then on he was called "the Pitiless".

[citation needed] When his brother died in 1417 and was succeeded by his daughter Jacqueline as countess of Holland and Hainaut, John the Pitiless rejected holy orders and surrendered his bishopric.

His Court Marshal Jan van Vliet had allegedly poisoned the pages of the ducal prayer-book, and had already been executed in 1424.