Religion

Belief takes several distinct forms across the series. In the manga and Brotherhood, the most visible is Letoism, a sun-god cult centered on the town of Reole, alongside the far older monotheistic faith of the Ishvalan people. Standing apart from ordinary worship is the entity called the Truth, which presents itself as God to alchemists who overreach, together with the Eye of God that Father hungers to consume. The 2003 anime adds Christianity to this landscape, its Flamel emblem adorning the Elrics' clothing and armor.

Each system carries its own character. Letoism was pure fabrication, engineered by the priest Cornello, who used a Philosopher's Stone to fake miracles and pass himself off as a prophet of the sun god Leto, winning devout followers such as Rose. Ishvalan faith, by contrast, is sincere and deep-rooted, forbidding alchemy, promising reunion with the creator Ishvala after death, and enduring through prophets and survivors long past every attempt to wipe it out. The Truth is stranger still, describing itself as the universe and every law within it rather than a worshipped deity, a being no one actually prays to.

These faiths rise and fall with the story's events. Cornello's Letoism unravels once the Elric brothers expose his trickery, and the Homunculi later keep it alive through Envy's impersonation of the priest, stoking violence in Reole to feed the nationwide circle, until reconstruction leaves the cult all but extinct. Ishvalan religion survives its people's near-annihilation, carried forward by the remaining faithful, and the manga even seems to confirm its promised afterlife when Hohenheim is reunited with Trisha beyond death. Father's bid to swallow God ends in his own ruin, cast back through the Gate by the Truth. In the 2003 continuity, where the Truth is replaced by the Gate Children, Christianity is shown to have existed and lingered, hidden in a secret church and echoed by figures such as Clara posing as a nun.