George III was the third of the Hanoverian line to serve as king in England and the first born there. He served for 60 years, during which occurred the American Revolution, the French Revolution, the beginnings of the Industrial Revolution and a host of changes to the empire and politics at home. Assuming the throne in 1760, he soon embarked upon an effort to recoup lost royal power, most notably in the dismissal of the powerful William Pitt the Elder. As early as 1765, however, the monarch's performance began to be impacted by porphyria, a disease that affects the skin or central nervous system and can cause hallucinations, seizures and depression. In 1770, after dismissing a series of prime ministers, George III appointed Lord North, who held the position for ten years. The collaboration between the king and prime minister resulted in a series of policies that led inevitably to revolution and war in America. The Hanoverian monarchs were not noted for intelligence, but George III was the best of the lot. While being very slow to learn to read as a youth, George impressed his tutors with his dedication. As king, he laboriously read every word of every document brought to him, often to the consternation of his ministers. He was a staunch supporter of educational causes, developing a royal library (that later went to the British Museum) and maintaining an interest in science and scientific instruments. His particular interest in agriculture led to the moniker "Farmer George." George III was a devoted husband and father, siring 15 children. His illness incapacitated him on several occasions and in 1811 royal authority passed to his son as Prince Regent. George III died at Windsor Castle in January, 1820. At the time of his death he was blind, deaf and demented.