Well from what I heard, I think it was confirmed. He actually said it in the movie before “Love is an Open Door”. He was ignored by all of his brothers. He has 12 older brothers, and he was the youngest and some of his brothers ignored him for 3 years. He was what that call “the bastard son”, he wasn’t close to his throne, so he had to marry into the throne somewhere. He probably wanted to go to Corona before, but I am guessing he heard that Flynn married the only princess there. Then he went to the kingdom that was the closest. I don’t know much about Hans but I wish I did.
There were also headcanons that his mother abandoned him or even died, and before she died, she hated him them. There was a photoset on here on tumblr somewhere where it was another headcanon that Hans’ mother said “Oh Hans, if there was only someone out there who loved you” and he goes “mom?”… I don’t know but these stories, and even his known backstory is heartbreaking.
But nonetheless, he shouldn’t have tried to kill Elsa. Or Anna. That’s the only thing I don’t like about him, but his story is what gets me.