Hercules hometown of Thebes has had to pay a tribute every year to Erginus the King of the Minyans. This ticks Hercules off, so when he meets some Minyans on the road he cuts off their ears, noses, and hands. so this makes King Erginus mad, and he charges toward Thebes with his whole army behind him. Hercules isn't scared at all and raises an army of his own.
Eventually though Hercules archenemy Hera, Queen of the Gods, steps in to ruin his life. Hera hates Hercules because he's not the real son of her husband, Zeus. The Queen of the Gods gets seriously nasty and causes Heracles to go crazy and kill all of his children Heracles then feels more than a little guilty about killing his kids and all. Our hero goes to the Oracle of Delphi to figure out how to atone for the damage he's done.
The Oracle tells him that he has to submit himself to be the servant of King Eurystheus of Argos. If it wasn't for a trick of Hera's Heracles would've sat on. when hercules accomplished all of his labor he could go home and have an empty mind