OK.
International anything didn't exist until there was a sufficiently reliable transport system to take people about. Morphy, born in New Orleans, came to Europe and beat every one of the strongest European players except English player Howard Staunton, who carefully avoided playing him. World Championships didn't exist then, but by the 1890s, they did. Hastings 1895 was probably the strongest tournament ever held at that time, thanks to the existence of a workable transport network. I would think that there have been relatively few occasions since then that pretty well all the best players in the world have turned up at the same event.
Morphy's playing career was remarkably short, but he played some absolutely wonderful games. He was head & shoulders above the rest in terms of his understanding of the basic principles and is generally regarded as the first unofficial World Champion, but his career lasted barely more than 3 years. Whilst, obviously, there were very good players before him, he was the first intercontinental player and he beat everyone. He then went quietly mad and died in a mental institution whilst not very old. He is known as "the pride and sorrow of chess".
So, arguably, "modern" chess started with Morphy and has grown ever since.
