Who really discovered America?

The honest answer starts by rejecting the premise. The Americas were discovered and populated by Indigenous peoples who arrived at least 15,000 years ago, and likely earlier, building thousands of nations and tens of millions of people long before any European saw the coast. Any framing of a European discovering an already-inhabited hemisphere with a rich human history is a story told from one side of the ocean.

Among Europeans, the first to arrive was not Columbus but the Norse. Archaeological evidence at L'Anse aux Meadows in Newfoundland confirms a Viking settlement around 1000 AD, led by Leif Erikson, roughly five centuries before Columbus. Columbus himself, sailing in 1492, landed in the Caribbean and never actually set foot on the mainland of what is now the United States; he died believing he had reached Asia. His voyages mattered enormously because they were the ones that stuck, opening sustained and catastrophic contact between the hemispheres, but that is a different claim than discovery. So the layered answer: Indigenous peoples first by millennia, Leif Erikson first among Europeans, and Columbus the one whose arrival changed the world, for the Americas' original inhabitants, mostly for the worse.