Nelsan Ellis, who is best known for his groundbreaking role on HBO’s True Blood, has died. He was just 39 years old. 

Ellis' cause of death is related to complications from heart failure, according to his manager. 

Joe Manganiello, who also starred on True Blood, called Ellis a pioneer on Twitter today.

Crushed today by the loss of my friend and castmate Nelsan Ellis. He was a wonderful person, a pioneer, and a one of a kind artist. RIP pic.twitter.com/fvtquhIac7

— Joe Manganiello (@JoeManganiello) July 8, 2017

Ellis' movie roles included appearing in The Help, Get On Up, and The Butler. 

Octavia Spencer, who also starred in The Help, offered her condolences on Instagram. 

Just got word that we lost @nelsanellisofficial. My heart breaks for his kids and family. #RIPNelsanEllis. #brillIantactor #trueblood #getonup #thesoloist #thehelp. The first time I met him was on the set of the soloist and we were at rehearsal with a lot of the homeless cast members, and Nelsan was playing our counselor. He walked in wearing a pair of fitted camo cargo pants, a pristine white tshirt, a beret, and a denim jacket. Needless to say he was gorgeous, sexy. But his talent had me speechless. We became instant friends after that. He was sooooo funny. I miss him. #nelsanellis

A post shared by Octavia Spencer (@therealoctaviaspencer) on Jul 8, 2017 at 11:43am PDT

Ellis is survived by his grandmother, his father, and his son, Breon, and seven siblings.