Chapter 572: Van Hohenheim
Van Hohenheim was a deceptively ancient and extremely powerful Alchemist as well as the estranged father of Edward and Alphonse Elric. Van Hohenheim was also known as slave #23 and was a citizen of Xerxes and a regular human being who was employed by King Xerxes' alchemist.
This alchemist was an experimenter and managed to create a being, the Dwarf in the Flask, as a result of alchemy while using Hohenheim's blood.
Unknowingly, this created a bond between the Dwarf and Hohenheim.
The Dwarf gave the slave a name, Van Hohenheim, before allying with him in order to turn the citizens of Xerxes into a philosopher's stone without Hohenheim's knowledge. Once this was successful, Hohenheim, as a human, had over 500,000 souls within his blood, giving him great power and a body that never ages.
After that, in despair, he aimlessly went east and reached the country of Xing. When Hohenheim's alchemic knowledge was combined with the rudimentary form of alchemy being studied in Xing, Alkahestry was born. The Xingese people called him the "Sage of the West."
Eventually, Hohenheim left Xing and spent centuries abroad accumulating knowledge regarding the world's different customs and practices. He also continued his communication with the thousands of souls trapped within him, 536,329, until he learned all their names and heard all their pleas.
Once all of them had been heard they finally calmed down giving Hohenheim some peace of mind and he continued his endless journey throughout the country but continued speaking to the souls within him to keep them calm. He later arrived in the growing country of Amestris and settled for a time in a small East Area town known as Resembool.
Due to his devotion to Alchemy and his own internal conflicts, people around him seemed to have an impression that he was cold, but instead, he was an unexpectedly softhearted, kindly individual who was quick to give compliments but loath to accept them. Even after so many years, he still loathed himself because he thought of himself as a monster because he became a Human Philosopher's Stone.
He was resolved to find a way to end his immortality and grow old and die together with his beloved Trisha, but also feared failure and watching his family die.