Islands have been around since Pangea split. They were safe havens for pirates, hosted prisons, and were homes for the rich. There is even a continent that is made up of only islands. It is called Oceania. Some countries such as the Maldives sell islands to the rich.
Worlds Largest Islands
Greenland 823,000 sq. miles
New Guinea 309,000 sq. miles
Borneo, Indonesia 208,000 sq. miles
Madagascr 227,000 sq. miles
Baffin Island, Canada 196,000 sq. miles