help needed!

Columbus and the Discovery of America?

There is very good evidence that sailors from Mali in Africa established a colony in the 1200s and 1300s in South America (though never contacted Mali again), Japanese sailors probably sailed the coast of the Americas prior to that, the ancient Phoenicians and Egyptians also may have made it to the Americas, Polynesian sailors from the South Atlantic made it to South America and the Vikings definitely made it to North America and Greenland .... so, it seems everybody at some time discovered America, so is Columbus important and if so why?  Use any of the info from the course or just your opinion.  Happy intellectual hunting.