The exact date for the creation of the Romefeller Foundation is unknown and its membership is just as secretive. The Foundation's membership consists of aristocrats and royalties across Europe and possibly the world. The activities of the Foundation may not be explicitly known to the world at large, but the results of their activities are recorded throughout history. The Foundation has secretly manipulated world affairs for centuries and so the true extent of their activities can't be known.
In the After Colony years, the Romefeller Foundation continued in their manipulation of world affairs including inciting conflict between nations since its members owned the munitions factories and supply routes necessary for most nations to wage war against one another. When the United Earth Sphere Alliance was formed the Foundation gladly supported it and began to place its members in the upper echelons of the Alliance's leadership. This would make the Foundation the defacto rulers of the Earth Sphere.
As time went on the Foundation slowly but surely pushed for military action towards the Colonies in order to gain complete control over Earth and Space. The military wing of the Foundation, the Organization of the Zodiac, or OZ became an integral part of the Alliance Military giving the Foundation defacto political and military control of the Earth Sphere.
By AC 195, the leader of Romefeller was Duke Dermail, the uncle of Treize Khushrenada and the grandfather of Dorothy Catalonia. It was Duke Dermail who engineered the overthrow of the Alliance by using the coming of the Gundams as an excuse to go to war with the Colonies. OZ became the prime target of the Gundam Pilots while the Foundation continued to influence the course of the world's politics.
Romefeller was beginning to solidify its control over the world by bringing more nations into its fold when the Sanc Kingdom came back into existance. The Sanc Kingdom continued spreading the ideal of total pacifism at a time when some were becoming war-weary. This began to draw some nations away from the Foundation and so it began to try and discredit or destroy the Sanc Kingdom. Duke Dermail realized that the leader of the Sanc Kingdom, Relena Peacecraft, was able to capture the attention of and persuade world leaders, and that she was someone who the people would follow. Thus, a plan was executed that resulted in the invasion and surrender of the Sanc Kingdom. Relena was taken to the Foundation's headquarters in Germany where Dermail made her Queen Relena of the new nation the Foundation engineered, the Earth Sphere Unified Nation. Duke Dermail's plan worked too well and the Foundation began to listen more to Relena than to him and was sent to space. During his trip, his shuttle was attacked and he was killed. With his death the Foundation began to falter and with the end of the war and the death of Treize Khushrenada the Foundation ceased to exist.