March 4 + Saint Casimir of Poland

Casimir was the third of thirteen children born to King Casimir IV of Poland and Elizabeth of Habsburg, an Austrian princess, daughter of Emperor Albert II.

From the age of nine, Prince Casimir and his brother Vladislaus were educated by the Polish priest Jan Długosz. The boys were taught Latin and German, law, history, rhetoric, and classical literature. Długosz was a strict and conservative teacher who emphasized ethics, morality, and religious devotion. Under the holy man, the young prince, already devout from infancy, embarked upon the pursuit of sanctity. Giving himself up to devotion and mortification, he often spent part of the night in intense prayer and meditation. Rejecting even ordinary comforts, he slept little, and when he did sleep, he lay on the floor not on a royal bed. Prince Casimir also had a great devotion to the Blessed Virgin Mary.

The prince was known for his intelligence, capacity, wisdom and charm. For four years, while his father was away in Lithuania, he assumed the King's position. Around this time his father tried to arrange a marriage for him to Kunegunde of Austria, daughter of Frederick II, but the prince refused, choosing to remain celibate.

While on a journey to Lithuania, Casimir succumbed to a severe attack of lung trouble (most likely tuberculosis) and died at the court of Grodno on March 4, 1484 at the age of 25. He was buried with his favorite song, a Latin hymn to Mary called "Omni die dic Mariae" which we know as "Daily, Daily Sing to Mary." Because of his love for the song, it is known as the Hymn of Saint Casimir.