A wealthy Moscow textile merchant, Morozov started buying art in a modest way in 1900 until, on a trip to Paris, he developed a taste for the avant-garde. Meticulous and highly discerning, he acquired works by the likes of Monet, Pissarro, and Cezanne. Unlike his friendly rival Sergei Shchukin, he collected Russian as well as European art. Altogether he spent 1.5 million francs on 486 paintings and 30 sculptures?more than any other collector of the age. Natalya Semenova traces Morozov’s...