The Knights of Saint John, also known as the Order of St. John, is a Christian military order founded in the 11th century. Originally established to provide care for sick and injured pilgrims in the Holy Land, the order evolved into a military force during the Crusades. Its members, known as knights, took vows of poverty, chastity, and obedience. Over the centuries, the order expanded its activities to include charitable work and healthcare. Today, the Knights of Saint John continue to operate in various countries, focusing on humanitarian efforts and supporting the sick and needy, while maintaining their historical traditions.