Juan Gris was a Spanish painter and early pioneer of Cubism whose work integrated rich color harmonies into compositions of angular shapes. Alongside Pablo Picasso, Georges Braque, and Fernand Léger, Gris challenged the traditional rendering of space and volume in painting. His hallmark technique of breaking up pictorial space through concentric angles is evident in his Portrait of Pablo Picasso (1912). “Cubism is moving around an object to seize several successive appearances. Which fused in a single image, reconstitute it in time,” the artist once explained. Born José Victoriano González-Pérez on March 23, 1887 in Madrid, Spain, he studied engineering at the School of Arts...