He is the youngest state alchemist in the history of the fictional country of Amestris. His left leg was severed after a failed attempt to resurrect his dead mother, while his right arm was amputated in exchange for saving his brother's soul; this happened due to the principle of "equivalent exchange", which states that in order to obtain something, one must sacrifice something of equal value. His lost limbs were replaced with sophisticated prosthetics called "automail".