
The old man is the Lord Commander
of the Night's Watch.
Game of Thrones Season 1, Episode 7

Lord Commander,
Game of Thrones Season 1, Episode 8

I'm Lord Commander of the Night's Watch.
Game of Thrones Season 5, Episode 3

It's the Lord Commander!
Game of Thrones Season 6, Episode 1

You are the COMMANDER of the Unsullied.
Game of Thrones Season 4, Episode 3