11 April - According to tradition, Stanislaus was born in Szczepanów, a village near the small town of Brzesko in Lesser Poland. The exact date between 1034 and 1040 is not certain, probably in 1039.

He is said to be the only child of a pious noble couple, Wielisław and Bogna. His parents sent him to the Cathedral School in Krakow under the protection of Bishop Aaron. From there he was sent to the school in Gniezno and then abroad, probably to Liège, then a great centre for the development of theological sciences and the reform of the Church.

Called back to Poland by the new Bishop of Krakow Lambert Suła, he was ordained priest and remained attached to the bishop's curia. He directed the cathedral school and the library of the Wawel Cathedral. The Polish prince Bolesław made him one of his chaplains. From then on Stanislaus worked at the bishop's chancellery. After the death of Bishop Lambert, Stanislaus was appointed as his successor in 1072 and thus became one of the first bishops of Polish origin. Initially, the collaboration between Duke Bolesław II and the bishop went very well.

The reasons for the conflict between Stanislaus and Bolesław II are not well known. According to Wincenty Kadłubek, Stanislaus defended the unfaithful wife of a knight who had accompanied the king in his campaign against the Kiev Rus'. What is certain is that Bolesław He was waging a war in the East and this long military action against the Russians demoralized his soldiers who began to desert. Furious, the king returned to Krakow and began to render justice. The deserters were executed and their wives cruelly condemned. Stanislaus denounced the repression, but Bolesław He did not accept that his authority should be challenged.

The king did not hesitate to massacre the bishop in the middle of the religious service while he was at the altar of the church of Skałka. After the death of his victim, Bolesław He ordered his body to be torn apart. According to the legend his dismembered body miraculously reassembled afterwards.