The Knight Hospitaller is a member of a military religious order, formally the Knights Hospitallers of St John of Jerusalem, so called after the dedication of their headquarters in Jerusalem to St John the Baptist. From 1310 they were known as the Knights of Rhodes, from 1530 the Knights of Malta. They began in c.1070 with Muslim permission to run a hospital for sick pilgrims in Jerusalem, and were made a formal order when the city fell in 1099 to the First Crusade. They adopted a black habit bearing a white eight-pointed (Maltese) cross. Under the first Master their function became primarily military and spread to Western Europe.
They followed the Augustinian rule and were divided into three classes: knights, chaplains, and the serving brothers. When they were driven out by Saladin they went to Acre, only to be expelled a century later when Cyprus became their headquarters. In 1310 they captured the island of Rhodes and retained it till 1522. Given the island of Malta by Emperor Charles V they held it, having fought off the assaults of the Turks, until it finally fell to Napoleon I.
By this time the order had lost its former influence. Some members moved to Russia where Paul I was made Grand Master. His death in 1801 led to a period of confusion. The English branch of the order was revived in the 1830s and today cares for the sick.