Van Hohenhiem is the father of Edward and Alphonse Elric in Full Metal Alchemist. At the beggining of the series we know that Van was a man who deserted his family because that was the 2 Brothers beliefs. but they didnt know who their father really was and why he left.
Van Hohenhiem is a living philosphers stone. that power was given to him by Father asa gift for letting him borrow his appearance and setting him free. This power stopped him from aging and gave him the power to do alchemy without making a transmutation symbol.
At the beginning of the series, I think many readers think that he was a cold hearted person because he left his family, but he later in the series he returns and it shows more of his personality. He is a nice person overall, and he is trying to fix his mistakes from the past. He kind of reminds me of Endeavor, but endeavor was more evil then him(But he is trying to fix his mistakes).
He isn’t very emotional in front of others, but he loved their Mom very much. He didn’t want to leave them, but he wanted to find a cure for the philosopher stone in him, he wanted to grow old with them, he didn’t want his sons to see him not age while they did.
He also wanted to get rid of father, who was brought to life using Hohenhiem’s blood in the past. He knew he was the source of the problem and was able to accept it, and he tried to make up for his mistakes of the past.
Hohenhiem is capable of the same alchemy done by the homunculi, he is very strong compared to other alchemists. but even though he has power, he doesn’t use force on others unless he has to.