Complex sentence: The California Plein-Air Revival is an art movement that began in the 1980s and its artists were inspired by the revival of interest in the works of the California Plein-Air School of 1900--1940.
Split into simpler sentences: The California Plein-Air Revival is an art movement that began in the 1980s. Artists were inspired by the renewed interest in the works of the California Plein-Air School of 1900--1940.