Henryk IV Probus
On 30 September 1288 Leszek II the Black, Duke of Kraków, Sandomierz, and Sieradz, died childless . His death launched the outbreak of war in Lesser Poland. The Kraków knighthood were in favor of Bolesław II of Płock, while the Sandomierz knighthood supported his brother Konrad II of Czersk; on the other hand, the middle-class citizenry favored Henryk IV Probus, Duke of Wrocław.