History tells us that the Templars were a medieval military order first known as the Poor Fellow-Soldiers of Christ and of the Temple of Solomon. History goes on to say that it existed for roughly two centuries in the Middle Ages and were closely tied to the Crusades in the Holy Land before being disbanded after their leaders were burned at the stake in France. That history is a lie, written by the Templars.
Like the Assassins, the Templars have existed in some form or another since the dawn of recorded history. Their ideology is centered around a perfect world, and their interpretation of that perfection often, if not always, involves absolute control over the freedom of individuals.
The Assassins respectfully disagree.
The Templar Order's control over the city of London, and by extension much of the British Empire, was like a sneak preview of the control they exert over the world today. In the eighteenth century, a Grand Master named Reginald Birch managed to sneak into the life of one of the most influential Assassins of the day, Edward Kenway.
Birch was appointed as one of Kenway's property managers but soon became a friend of the family, even going so far as to court Edward's daughter, Jenny. 'Court' is a polite word that I'm sorry we don't use as much today. In reality, all Birch wanted to acquire was Kenway's research into the First Civilization. However, Jennifer discovered the truth and informed her father, which forced Birch to send mercenaries to the Kenway mansion. Edward was killed and Jennifer was sold to Turkish slavers. Obviously.
To add insult to injury, Birch became the legal guardian to Edward's son, Haytham Kenway, and raised him as a Templar. With Edward out of the way, London was left without a significant Assassin presence and Birch wasted no time solidifying his Order's grip on the city. But that wasn't enough; he wanted access to Precursor sites and sent Haytham to the Colonies in order to try and secure one.
Birch's treachery was eventually discovered by Haytham and his sister, who murdered him. But by then, the Templar's control over London was absolute; industry, politics, they had their claws in every layer of society. The Templars in London went virtually unchallenged for over a century.
These days, the Templars are still pulling the strings. In the past, they were popes or royalty or politicians. Today, they operate behind the most insidious force of all: a corporation. The public face of the Templar Order is a multinational conglomerate known as Abstergo.