To get a man of the hour you need at the minimum a Heroic Victory. Next you also need the generals unit to get around 100-200 kills. Also a trigger in RTW was the captain himself getting at a minimum of 10 kills. Part of the reason why it's hard to get men of the hours when their not mounted.

If you know how to earn the "brave" line of traits, rinse and repeat that on a captian.