Granted Picasso’s Les Demoiselles d'Avignon, where you could see the transition into cubism, was from 1907. He continued to create famous abstract works well into the 50s. Dali’s famous The Persistence of Memory (the melting clocks) is from 1931.

It’s wild that people think of the abstract movement pre-1900s to me! Pre-1900 was the Impressionists, and with Art Nouveau coming in at the turn of the century.

The 1930’s was really primed for the abstract modern painters.