Oceania is a region centered on the islands of the tropical Pacific Ocean.
Digger Harkness, otherwise known as Captain Boomerang was born and raised in Australia. He was responsible for numerous robberies and break-ins and has been doing so since he was 18. After robbing much of Australia, he decided to go to the United States of America to commit more robberies and was apprehended by the Flash while there.
In 2015, footage was taken by a diving robot attempting to enter a wrecked ship in a trench in the Tonga Islands. The footage was cut short after Aquaman, startled by the intrusion, attacked and destroyed the camera before swimming off at high speed. The footage was later acquired by LexCorp in their research into the Metahuman presence on Earth.