As reported by Wikipedia:

"Michelangelo Merisi da Caravaggio (29 September 1571 – 18 July 1610) was an Italian artist active in Rome, Naples, Malta, and Sicily between 1593 and 1610. His paintings, which combine a realistic observation of the human state, both physical and emotional, with a dramatic use of lighting, had a formative influence on the Baroque school of painting.
Caravaggio trained as a painter in Milan under Simone Peterzano who had himself trained under Titian. In his early twenties Caravaggio moved to Rome where, during the late 16th and early 17th centuries, many huge new churches and palazzi were being built and paintings were needed to fill them. During the Counter-Reformation, the Roman Catholic Church searched for religious art with which to counter the threat of Protestantism, and for this task the artificial conventions of Mannerism, which had ruled art for almost a century, no longer seemed adequate.

Caravaggio's novelty was a radical naturalism that combined close physical observation with a dramatic, even theatrical, use of chiaroscuro. This came to be known as Tenebrism, the shift from light to dark with little intermediate value. He burst upon the Rome art scene in 1600 with the success of his first public commissions, the Martyrdom of Saint Matthew and Calling of Saint Matthew. Thereafter he never lacked commissions or patrons, yet he handled his success poorly. He was jailed on several occasions, vandalized his own apartment, and ultimately had a death warrant issued for him by the Pope."