St. Casimir was a prince of the Kingdom of Poland and of the Grand Duchy of Lithuania during the 15th century. Initially he wasn’t very religious, but as he began to see the dark side of politics, Casimir devoted himself more and more to prayer.
When Casimir was a teenager, his father wanted him to become King of Hungary and they even waged a military campaign to seize the throne. At first Casimir went along with his father’s wishes, but after witnessing the horrors of war and how power negatively affected many of his relatives, he refused to go on. Neither his father’s attempts to convince him nor the invitations of the Hungarians could dissuade him from his pursuit of a godly life. He dedicated the rest of his life to penance and was often found praying before the church doors were opened in the morning.
Father Alban Butler summarizes his life by saying, “The kingdom of God is with you! With what ardor ought [Christians] to devote themselves to make God reign perfectly in their hearts! How justly did Saint Casimir prefer this pursuit to all earthly kingdoms!”