I want to know the answer to the following question:
What was Marwan II's name before he became caliph?
All the background I'm provided with is that "Marwan ibn Muhammad, the future Marwan II, finally ended the war in 737 with a massive invasion that is reported to have reached as far as the Volga, but the Khazars remained unsubdued.". Is that enough to answer the question?
Answer: yes