Abstergo is one of the biggest modern day companies, functioning as the Templar's Front, although it is labeled as a pharmaceutical company, Abstergo and its predecessors are responsible for every Human Advancement in the past Millennia, which they came up with using Piece's of Edens. But Behind the Abstergo Front, the templars true mission is to control all humanity using their Animus Project to locate a piece of eden, launch it into space, and control humanity. This Project is EYE-ABSTERGO.
The founders of Abstergo designed the "Plan" in 1910, it was not until 1937 Abstergo was founded, but back then, it was a shadowy company and not very famous. Calculating every move to make sure the course of history goes their way, including calculated killings, Ruses and developments.
The Great Purge
Subject 4 Of the Animus was Daniel Cross, who was experimented on at an early age, and had a trigger planted in him, letting him go, he was inducted into the assassins, risen into their rank and killed their mentor, he returned to Abstergo and told them all the Assassin Camp locations, leading the templars into "The Great Purge" in which they killed most of the assassins.
As a plan to gain more research money, Abstergo Industries created Abstergo Entertainment, an addition to the original company, with the front of creating video games based on the many ancestors in Desmond's timeline(Aveline not included). It's other purpose is to locate First Civilization sites, such as the Temple, or the Observatory, as discovered in Assassin's Creed IV. Some of the employee's are secretly Templar agents, who are able to detain and take away if the researchers begin to get suspicious. Along with them, secret Assassin's, such as Shaun and John from IT, who work in plain sight.