England claimed sovereignty in 1690, and has maintained their sovereignty.
Argentina wasn’t even an independent nation until the 19th century.
The Falkland Islands belong to the Brits, the people who live and vote there, and they don’t speak Spanish!
They were first settled by the French. You can claim sovereignty. In those days just looking at a piece of land and they claimed it. We will have to agree to disagree on this one which is why the dispute will never end..