St Francis

Originally aspired to be a knight, St Francis who was from the Italian town of Assisi ended up being a prisoner of war and wasn't interested in his father's trade. One day, St Francis found himself at a run-down church at San Damiano where God told him while praying to "repair my church, which is falling in ruins" in which he did with his father's money. After this, he lived his life in poverty and preached the life of Jesus Christ to people. He had 11 followers who, like him, were dirty, poor and weren't smelling that great. Which is why at first the pope was reluctant to approve their religious Order but eventually blessed their Order after understanding their vow of poverty. This order is the Franciscan Order which adheres to the teachings of St Francis of Assisi. St Francis also helped another Assisi local called Clare set up one for women, now called the Order of the Poor Ladies (Order of St Clare).
St Francis of Assisi is the patron saint of Animals because he had a love for animals of nature as he would preach to animals with one moment in particular resulting in some birds singing together while he was talking before the birds flew up into the sky to form the sign of the cross. He was said to tame wild animals as when a vicious wolf was terrorizing the town of Gubbio, he made the sign of the cross and told the wolf not to hurt anyone else after which the wolf became tame and the town that had lost people and sheep to the wolf was saved.
St Francis also set up the first known Nativity scene to celebrate Christmas.
Two years after he died while singing Psalm 141, St Francis of Assisi was made a saint of the Catholic Church with his feast day falling on 4 October every year.