The Templars are the Assassin Brotherhood’s main rival in the Assassin’s Creed series.
The central conflict pits the Assassins, who value free will, against the Templars, who seek peace through control and order. Both groups operate across centuries, influencing governments, institutions, wars, and important historical events from behind the scenes.
The Templars are connected to the historical Knights Templar, but the games present a fictional continuation of that idea through the modern Abstergo organization. Abstergo uses advanced technology and public institutions to pursue Templar objectives in the present day.
Some games use earlier names for related groups. In Origins, the Templars’ predecessors are the Order of the Ancients, while Odyssey features the Cult of Kosmos. Those organizations are regional or historical branches within the wider mythology, not the franchise’s standard name for the main rival faction.