Retired General Rick was one of several Ricks candidates in the election for the next president of the Citadel of Ricks. He was the clear frontrunner of the election, leading the polls until the debate, where Candidate Morty took the lead and eventually won. (Although according to the guards, it was almost close enough to trigger a recount, indicating RGR came in a close second)
It was shown that he didn't take Candidate Morty very seriously and neither did the other candidates.
It's unknown if he was present and died during the destruction of the Citadel or left it and survived his likely demise.