Horace was originally a bartender at The Drunken Clam to Peter, Quagmire, Joe and Cleveland until he was killed off in Season 11 Save the Clam. He accidently been hit and killed by Jerome with a baseball.
As The Drunken Clam was about to shut down due it’s loss for their former bartender, Jerome was responsible for Horace’s death as he decides to get into his contract by taking over his business and run his own bar.