Paris!

From my review of Charles Murray's Human Accomplishment in The American Conservative:

French postmodernists will sneer at the very concept of objectively measuring greatness, but their brittle amour propre will be secretly salved by hearing that the most important city in Murray’s lists, by far, is Paris. It was the workplace for 12 percent of the 4,002 significant scientists and artists [in Murray's database of eminent individuals over the last 2,800 years].

I believe London was in second place, way back with 4%.

My published articles are archived at iSteve.com -- Steve Sailer