It's not directly related to General Mattis, but I would recommend reading Evan Wright's book "Generation Kill".
Which recounts his time being embedded with the 1st Recon Battalion, which was under the command of Mattis (Callsign Chaos) during Operation Iraqi Freedom.
The book even goes briefly into a famous moment in the invasion of Iraq were General Mattis fires one of his commanders during a siege of a city.
Amazing fact about that book and show: Sergeant Rodolfo "Rudy" Reyes ('Fruity' Rudy) finished his term with the military and decided to move to Hollywood and become an actor. A few years later, casting began for the miniseries based on the book, based on his tour. He tried out.
I would like to second the tv series Generation Kill. Brilliant show. Really highlights a lot of the ridiculousness of war. Not as serious nor on the same scale as Band of Brothers, but still good nonetheless.
Rudy is played by himself.