In Fullmetal Alchemist (2003 anime series) Fuhrer Bradley/King Bradley is a homunculus and is head of the military in Central. They say the Homunculi are created when an alchemist attempts human transmutation, which always fails and from those failures, a homunculus is created and is born to look like whoever they were suppose to be bought back as.
e.g. Alphonse and Ed tried to resurrect Trisha, their mother, and end up failing. Years later they run into her but she is known as Miss Douglas.
I can't remember how I know that Homunculi are suppose to look like what they were supposed to be resurrected as but what was King Bradley supposed to be?