Which medieval military order became famous as the Knights Hospitaller?

The medieval military order known as the Knights Hospitaller was the Order of Saint John.

The order began in Jerusalem as a charitable institution caring for sick and poor pilgrims. After the First Crusade, it developed a military role and became one of the most important Christian military orders in the eastern Mediterranean. Its members were also called Hospitallers, reflecting the order’s hospital origins.

After the fall of Jerusalem in 1187, the order moved its headquarters to Acre. When Acre fell in 1291, the Hospitallers relocated first to Cyprus, then to Rhodes in 1309, and later to Malta in 1530. These moves helped create the names Knights of Rhodes and Knights of Malta.

The Hospitallers are often confused with the Knights Templar, another crusading order. Both fought in the Crusades, but the Hospitallers retained a strong charitable and medical identity alongside their military duties. The order still exists today as the Sovereign Order of Malta.