Passage: When Turkey entered the World War, he was working at the High Command in Constantinople. He later served as the divisional commander in 3rd Ottoman army on the Russian border, thereby also involved in operations against the Armenians who were allied to the Russians. Later, he was one of the  senior commanders of the Ottoman forces in Mesopotamia, now Iraq, during World War I.

Question: What division was he made commander of?
3rd Ottoman army