Bobby Fischer, the reclusive chess genius, died at 64 due to kidney failure in a Reykjavik hospital.
He was born in Chicago and raised in Brooklyn, becoming a grand master at 15.
What happened?
Fischer faced criminal charges in the US for playing a 1992 rematch against Boris Spassky in Yugoslavia.
He renounced his American citizenship and later moved to Iceland in 2005.
Fischer's spokesman, Gardar Sverrisson, announced his death on Friday.
Why it matters for Bobby Fischer
Fischer's reputation as a genius of chess was soon eclipsed by his idiosyncrasies, including his anti-Semitic comments.
Garry Kasparov, the former world chess champion, described Fischer's ascent in the chess world as "a revolutionary breakthrough".
What comes next?
Fischer lost his world title in 1975 after refusing to defend it against Anatoly Karpov.
He dropped out of competitive chess and largely out of view, emerging occasionally to make erratic comments.
Kirsan Ilyumzhinov, president of the World Chess Federation, called Fischer "a phenomenon and an epoch in chess history".
Fischer played an exhibition rematch against Spassky on the Yugoslav resort island of Sveti Stefan in 1992.
He was arrested at Japan's Narita airport in 2004 for traveling on a revoked US passport.
Fischer spent nine months in custody before the dispute was resolved when Iceland granted him citizenship.
He championed his concept of random chess, in which pieces are shuffled at the beginning of each match.
Fischer told reporters in 2005, "I don't play the old chess, but obviously if I did, I would be the best."
He was born on March 9, 1943, and became an American chess champion at 14.
Fischer's longtime companion, Miyoko Watai, survives him.