The fellow on the left is a fighter from Reaper miniatures with scale mail armor and a huge sword in one hand. The one on the right is the second of a three man knight set for Rackham Templars that I have. Still have one more to paint up. The Rackham dude is so old that they don't even make him anymore. Heck, they haven't made him in metal in a while and now the plastic versions are gone too.
While the knight may look slightly taller, note that he's on an actual base that gives him a height advantage eh?