The Knights of St. John, also known as the Order of St. John, is a medieval Catholic 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. They became known for their role in defending Christian territories against Muslim forces. Over the centuries, the Knights of St. John expanded their influence, establishing hospitals and fortifications. They eventually settled on the island of Malta, where they became known as the Knights of Malta. The order continues to exist today, focusing on humanitarian efforts and charitable work.