Short answers, pulled from the story.
Pankration was introduced to the Greek Olympic Games in 648 BC. It combined boxing and wrestling with additional techniques including kicks, joint locks, and chokes, making it one of the most comprehensive combat sports in the ancient world.
Ancient pankration had only two rules: no eye gouging and no biting. Sparta was the one exception, where both were permitted. There were no weight divisions and no time limits. A contest ended by submission, signalled by the competitor raising an index finger, though judges could also stop a bout or declare a draw.
Arrhichion of Phigalia won a pankration competition at the Olympic Games after already being dead. Caught in a chokehold, he broke his opponent's toe or ankle, causing the opponent to submit from pain. The referee raised Arrhichion's hand in victory only to discover he had died from the chokehold. His body was crowned with the olive wreath and returned to Phigaleia as a hero.
Pankration was part of the training of Alexander the Great's Macedonian phalanx. The Athenian Olympic champion Dioxippus, who won the Games in 336 BC, served in Alexander's army and used pankration skills to defeat an armed soldier named Coragus in single combat while carrying only a club.
Pankration was abolished in 393 AD by edict of the Christian Byzantine Emperor Theodosius I. It was banned alongside gladiatorial combat and all pagan festivals, ending more than a thousand years of competition.
Greek-American combat athlete Jim Arvanitis introduced Neo-Pankration to the martial arts community in 1969 and was featured on the cover of Black Belt magazine in 1973. In 2010, pankration was accepted by FILA, now known as United World Wrestling, as an associated discipline, and was first contested at the World Combat Games that same year.