St. Francis of Assisi is one of the most venerated religious figures in Roman Catholic history. He founded the Franciscan orders, including the Poor Clares and the lay Third Order. He and St. Catherine of Siena are the patron saints of Italy, and he is also the patron saint of ecology and of animals.
He is the patron saint of the animals because he loved all creatures and allegedly preached to even the birds. St. Francis of Assisi is quite possibly one of the most universally beloved saints, not only by Catholics, but by many Christians and non-Christians alike. Well-known for his dedication to serving God by embracing poverty, living simply, and treating all of God’s creation (from humans to animals to nature) with respect, St. Francis’ message is one that appeals to the yearnings of the human heart for true freedom and unfailing love. In recent years, many congregations have started to bless pets and other animals as a way to mark this day and honor his spirit.