A popular “King of the Hill” voice actor was shot dead Sunday night, allegedly by a neighbor after a fiery dispute, and it seems tensions between the two men had been building for years … TMZ has learned.

Jonathan Joss — the actor best known for voicing John Redcorn on the popular animated FOX sitcom — was shot and killed on his Texas property, allegedly by Sigfredo Alvarez Ceja, who is now in police custody.

Neighbors on the San Antonio block where the shooting occurred tell TMZ … Joss’ home burned down in February, but he returned Sunday to collect a victim’s fire fund check. While there, he found the skeleton of one of his dogs killed in the fire, and it sent him into a rage — he started yelling at anyone he saw in the area.

We’re told that led to a spat with Ceja, who lives two doors down … and shortly thereafter, the suspect allegedly drove over and shot Jonathan before fleeing. Emergency crews arrived on the scene and attempted to save the actor.

We hear the two men have a history … and allegedly have been in both verbal and physical fights in the past. Neighbors say Joss’ rants were actually a fairly common occurrence, and police had been called on him several times prior to his house burning down.

Neighbors also told TMZ the actor would do kooky stuff … like bang pans on his roof in the middle of the night.