A Templar is a knight of a medieval spiritual order of knights
The Order of the Templars (also known as the Temple Order) was a (Catholic) order of monks who, at the time of the Crusades, carried out a holy war against the Muslims in the Holy Land. The order was created around 1115 and officially recognized by the Catholic Church in 1129. In the 200 years that the order has existed, the Templars were powerful and rich enough that the French king (Philip the Clean) did everything to get rid of them.