Pope Leo XIII (born Vincenzo Gioacchino Raffaele Luigi Pecci) was the head of the Catholic Church from 1878 to 1903. He decreed that a prayer to St. Michael be said at the end of "low" Masses, along with the Salve Regina. He was born in Carpineto and was the sixth of seven sons of Count Lodovico Pecci and his wife Anna Prosperi-Buzi. As Pope, he used his authority to revive Thomism, a theology based on Thomas Aquinas' thought, and issued an encyclical Aeterni Patris which laid the cornerstone for a great social edifice he was about to construct in his following encyclicals.
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