The Earth Federation Forces (E.F.F.) are the military branch of the Earth Federation government in the Universal Century timeline.
Like the Earth Federation, the origin of the Earth Federation Forces predates the Universal Century. By some accounts, it was formed from the United Nations Forces in A.D. 2009. Compared to the former United Nations Forces, the EFF was given far more power, allowing the Earth Federation government to respond to regional conflicts and natural disasters far more efficiently.
In U.C. 0079, the Principality of Zeon declared war on the Earth Federation. Due to Zeon's use of new tactics and weapons, including mobile suits, Minovsky particle interference, and even the use of a space colony as a projectile, the Earth Federation Forces was completely caught by surprise and suffered massive casualties in the early stage of the war. To make matters worse, General Johann Abraham Revil was captured during the disastrous Battle of Loum.