Michael Oversteegen is a fictional character in the Honorverse, a series of military science fiction novels written by David Weber. He is a Rear Admiral in the Royal Manticoran Navy, and commands a battlecruiser squadron.
He first appeared in The Service of the Sword as a Captain (junior grade). Following the events of that novella (including the Battle of Tiberian) he was promoted to Captain of the List, and appeared again in Crown of Slaves.
At the beginning of The Service of the Sword, he was young for his rank, having just been promoted 'out of the zone' (lacking the seniority ordinarily required) from Commander to Captain (junior grade). He is a Manticoran aristocrat, fourth in line of succession to the Barony of Greater Windcombe, and his mother was the second cousin of Michael Janvier, Baron High Ridge. He physically resembles High Ridge.
While he was widely assumed to have gotten as far as he had on patronage, appearances were deceptive and he proved to be a brilliant and decisive commander, similar to Aivars Terekhov and Honor Harrington herself.
He is rumoured to be the reincarnation of his great-grandfather, a notorious duellist.
At the beginning of At All Costs, Oversteegen was still a captain, although he was given the most prestigious battlecruiser command, the new Nike. He is later promoted to Rear Admiral and given command of Battlecruiser Squadron 81, Eighth Fleet.