The Barton Foundation was a colony based organization seeking domination of the Earth Sphere and the overarching antagonists of Mobile Suit Gundam Wing and its OVA epilogue series Endless Waltz.
It was a political entity run by Dekim Barton, the patriarch of the Barton family. The Barton Foundation funded the efforts of the Gundam scientists to construct five superior Mobile Suits. The Foundation was also behind the scientists efforts to find and train pilots for four of them, as Dekim's own son Trowa Barton was intended to pilot the Heavyarms Gundam.
The Barton Foundation was also responsible for the funding and construction of the colony X-18999 in the L3 Colony Cluster. This colony was the intended first strike of Foundations infamous Operation Meteor.
After the Earth Sphere United Nations began a demilitarization effort following the end of war between the Earth government and the colonies, the Barton Foundation gathered the remaining supporters of armed conflict and other former members of OZ to form the Mariemaia Army and began their own bid to conquer the Earth Sphere.
The Barton Foundation funded the efforts of five scientists to create superior mobile suits, Gundams, to use for their plans to dominate the entire Earth Sphere. However, the five scientists disagreed with the Barton Foundation's plans of conquest of the Earth Sphere and allowed the Gundams to be seized by the Colony Liberation Organization to be used in the fight for colonial independence.
After the downfall of the Romefeller Foundation, the destruction of the White Fang and OZ, and ESUN deactivating the remaining Mobile Suits to usher in a new era of peace, the Barton Foundation made its move. Using his granddaughter Mariemaia Khushrenada, the daughter of Treize Khushrenada, as a figurehead, Dekim Barton rallied former members of OZ and other soldiers who supported militarization to form the Mariemaia Army, which purported to fight for the ideals of Treize when in fact it was little more than a private military for the Barton Foundation. On the Christmas Eve of A.C. 196, the Barton Foundation began its takeover of the Earth Sphere by kidnapping ESUN Foreign Minister Relena Darlian and threatening to drop the X-18999 space colony on Earth if ESUN refused to submit to the rule of Mariemaia.