George III (June 4, 1738 - January 29, 1820) was King of Great Britain (1760-1801) and King of the United Kingdom of Great Britain and Ireland until his death. His life and reign, which were longer than any other British monarch before him, were marked by a series of military conflicts involving his kingdoms, much of the rest of Europe, and places farther afield in Africa, the Americas and Asia. Early in his reign, Great Britain defeated France in the Seven Years' War, becoming the dominant European power in North America and India. However, many of Britain's American colonies were soon lost in the American Revolutionary War. In the later part of his life, George III had recurrent, and eventually permanent, mental illness. After a final relapse in 1810, a regency was established, and George III's eldest son, George, Prince of Wales, ruled as Prince Regent. On George III's death, the Prince Regent succeeded his father as George IV. He died in 1820 at the age of 81. Engraving by William Pether, 1762.