Juan Calvino, known as John Calvin in English, was a prominent theologian and reformer during the Protestant Reformation in the 16th century. Born on July 10, 1509, in Noyon, France, he became a key figure in the development of Reformed Christianity. His teachings emphasized the sovereignty of God, the authority of Scripture, and the concept of predestination. Calvino's most significant work, the Institutes of the Christian Religion, laid the foundation for many Protestant beliefs. He spent much of his life in Geneva, Switzerland, where he established a theocratic government and influenced the city's religious practices. His ideas continue to impact various Christian denominations today.