If you Throw Your Hat Into The Ring you are signalling your intention to take up a challenge or to join an event or enterprise. The phrase has its origins in the days of prize-fighting. Prize-fighters would tour the country with travelling fairs, giving locals the chance fight them to win money. A local would enter the competition by throwing his hat into the ring. It would first be placed in a pile with the others and later shown to the crowd as an invitation for the owner to step forward to fight.