St Casimir
Polish prince. Patron of Lithuania. Casimir was the third son of King Casimir IV of Poland. Born in 1458, he was educated by John Dlugosz, canon of Krakow, the mediaeval capital of Poland. When Casimir was just 13 there was an attempt to place him on the throne of Hungary. This failed and he was banished to a castle outside the city. The court then tried to pressurise him into marrying a daughter of the Emperor Frederick II, but he refused, saying that he wanted to live a life of prayer and celibacy.
From 1481-83 he ruled over much of the country and was considered very wise and just. He died of tuberculosis at the age of 26, in 1485, and was buried at Vilna. Many miracles were reported at his tomb. He was canonised by Pope Leo X in 1541. He was buried with a copy of the hymn by St Bernard of Cluny: 'Omni die dic Mariae' which is sometimes called St Casimir's hymn.
St Casimir was often invoked by Lithuania during the conflicts with Russia during the 16th and 17th centuries.
Listen to one modern version of 'Omni die dic Mariae' here: www.youtube.com/watch?v=0DdesDiVgQQ
and an arrangement by Gorczycki here: www.youtube.com/watch?v=hdRdN7PLLVQ