After a revolution broke out in the fictional country of San Diablo, two factions emerged; a democratic one and a communist one. The leader of the communist faction was Santiago Chavez y Rivera, often called the Executioner for his harsh firing squad-style executions. His army was formidable, containing fighter planes, tanks, and armed forces. Much of his legion was defeated or destroyed by Thor, with help from the democratic faction of San Diablo.
Realizing he had lost, the Executioner attempted to flee along with his stolen gold and cash, presumably from the San Diablo treasury. In the end it was his own men, seeing that they had been betrayed, who gunned him down - ironically in front of his own execution wall.
The character of the Executioner is a classic example seen during the Cold War called the "Red Scare," where writers would use anti-communist propaganda in their story telling.