Sir James Thornhill was an English painter in the 17th century who worked in the Italian baroque style. He is best known for his large-scale paintings at the Royal Hospital in Greenwich called the "Painted Hall" which took him 19 years to complete. Thornhill developed a technique of painting on dry lime plaster with lead oxide and then oils which allowed for corrections. He included himself in the Painted Hall paintings to memorialize his unpaid work. Thornhill's mastery of the Italian baroque style and his monumental projects like the Painted Hall established his reputation as a leading English history painter of his time.