Paul Morphy was nothing but the embodiment of romantic attacking chess, as he was the strongest player of the 1850s and considered the best player in the 19th century. Even if there wasn’t any official world championship title while he was active, he was many years ahead of his competition and has remained as an unofficial world champion.
Morphy won the 1857 American Chess Congress, and he then suddenly decided to travel to Europe in 1858, winning every single match he played against the world’s leading players. He was the one that taught the chess world a hard lesson about sacrifices, development, attack, accuracy, and many other things.
His famous “Opera Game” is seen as one of the most famous chess games of all time, and it is studied up to this day.