The character name "Carl Marznap" is a reference to real life serial killer/arsonist Carl Panzram.
Both Michael Cudlitz (Jim) and Pruitt Taylor Vince (Carl Marznap) have appeared in the Walking Dead. Vince in season 2 and Cudlitz from season 4.
Actor Michael Cudlitz and writer/producer Frank John Hughes costarred in the HBO miniseries Band of Brothers.