St. Peter of Verona was born in 1205 to Cathars. Cathars believed that there were two gods, the good New Testament God of the spiritual world, and the bad Old Testament God of the material world. Everything of the material world came from Satan and was evil, including sacraments. However, Peter was educated in Catholic schools and at the University of Bologna. He became a Dominican friar and preacher. In 1251, he was appointed as inquisitor of Lombardy, where many Cathars lived. He converted many Cathars but also made several enemies.
On April 6, 1252, he and another friar named Dominic were travelling to Milan when they were attacked by hired assassins. Peter was struck in the head with an ax. He died in the road after writing the opening line of the Apostles’ Creed in his own blood (Credo in unum Deum). Dominic died five days later. Peter was canonized the next year; this was the fastest papal canonization in history. Peter came to be known as St. Peter Martyr. One of his assassins repented and became a lay Dominican.
St. Peter of Verona’s feast day is April 6. (From 1586 to 1969, his feast day was April 29 because his death date would often conflict with Easter.) I find his icons one of the goriest, as he is often depicted with the ax still cutting into his head.