who discovered queensland

Trick question: no one "discovered" Queensland—First Nations peoples have lived there for tens of thousands of years.

The first recorded European to make landfall in what is now Queensland was Dutch navigator Willem Janszoon in 1606, on the western side of Cape York.

James Cook later charted the eastern coast in 1770, did some enthusiastic naming, and sailed off before the sandflies formed a union.

As a colony, Queensland officially separated from New South Wales in 1859—long after the locals had the place well sorted.