19/27) Jax Teller has one of the highest kill counts of the entire series, with 45 direct murders by the finale, 26 of which were named.
20/27) The character Lee Toric was killed early on season 6 because the shooting of Vikings was sooner than originally expected, so Donal Logue could only do four episodes.
21/27) In the episode where Gemma and the Sons are at her father's house in Oregon, Tig offhandedly mentions to Gemma, played by Katey Sagal, who is in hiding as a fugitive due to a federal warrant for her arrest, that in order to go unnoticed maybe she should go redhead for awhile. Gemma then states, disgustedly, that she would rather shave her head than dye it red.
This is most likely a tongue-in-cheek reference to Katey Sagal's character Peg Bundy from her show Married with Children who was known for her large bouffant red hair.
22/27) Walton Goggins' role came about because he read an interview where creator Kurt Sutter explained why Michael Chiklis and Goggins hadn't guest starred on the show like many actors from The Shield. Sutter explanation was that the actors were too associated with their characters from the show, telling Goggins "you'll only be on the show if you've got tits and a wig."
Goggins replied "Let's do it!" and appeared on the show as a transvestite.