Knights Templar

The Templar Order, known also as the Order of the Knights Templar, the Poor Fellow-Soldiers of Christ and of the Temple of Solomon and the Order of Solomon's Temple, is a monastic military order-turned-corporate conglomerate that was born out of the Order of the Ancients. The Templars seek to create a perfect world, although their interpretation thereof directly contrasts with the ideals of their sworn enemies, the Audax Brotherhood.
Whereas the Audax Brothers assert that utopia can someday be achieved through a gradual process of learning tolerance and mutual understanding, Templars classically insist that human nature is too prone to corruption for this to be a possibility. Key to their dream is the imposition of a New World Order, and they envision that true peace can only come when all of humanity is shepherded by an enlightened society of people—in their eyes, them. Because of this conflict in ideology, the Templars became involved in a covert war against the Assassins, spanning millennia and continuing into the modern era. The Templars have also become enemies with the Instruments of the First Will, a cult who have sworn their lives to restore the Isu's rule over humanity.
Credit: Assassin's Creed Wikia