Why did Historia's mother hate and reject her? Other than her being a bastard child, was any reason given as to why Historia's mother hated her and disowned her?
The reason was that Historia is Rod Reiss's child. Since Historia was his child, she has the ability to obtain the abilities of the Coordinate and use them to the fullest. This was the reason that the Military Police's First Interior Squad had to murder Historia and her mother in order to ensure that power would not fall into the hands of people the central government could not control.

Therefore, Alma hated Historia as Historia's existence would lead to her death.


  Historia Reiss - She carried deep resentment towards her daughter, even more so before Kenny slit her throat, as Historia's existence is the reason she had to die.