Michelangelo Merisi da Caravaggio revolutionized painting by introducing 'Tenebrism,' an extreme form of 'Chiaroscuro' (light and dark). He used dramatic, spotlight-like lighting to pull his subjects out of deep, pitch-black backgrounds, creating an intense psychological and theatrical effect. Caravaggio was notorious for using ordinary people—beggars, laborers, and even known prostitutes—as models for saints and biblical figures, which often caused scandal. His work, such as 'The Calling of St. Matthew,' rejected the idealized beauty of the High Renaissance in favor of a gritty, 'dirty-fingernail' realism. Despite his violent personal life and early death, his influence (called 'Caravaggism') spread across Europe, directly inspiring masters like Rembrandt, Velázquez, and Rubens.