You're probably familiar with caricatures of the Knights Templar, a group of 14th-century militaristic monks.

In "Indiana Jones and The Last Crusade," a Templar guards the Holy Grail -- the cup that Jesus Christ drank from at the Last Supper. "Monty Python and the Holy Grail" lampoons the group's search for the Grail during the Crusades.

That's the Hollywood version.
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Templars

The Da Vinci Code

The Holy Grail