catherine was born in stettin, which was a part of the kingdom of prussia at the time. she was the daughter of prince christian august of anhalt-zerbst and princess johanna elizabeth of holstein-gottorp. she had five brothers and sisters. she married her cousin peter iii (who, like catherine, was german) at age fifteen, and became empress of russia at age 32. she was educated in three languages (russian, german and french). she grew up as a lutheran (protestant). when she married peter, she changed to the russian orthodox church.