Charles III (Carlos Sebastián de Borbón y Farnesio; 20 January 1716 – 14 December 1788) was King of Spain in the years 1759 to 1788. He also was Duke of Parma and Piacenza, as Charles I (1731–1735); King of Naples, as Charles VII; and King of Sicily, as Charles V (1734–1759). He was the fifth son of Philip V of Spain and the eldest son of Philip's second wife, Elisabeth Farnese. He was a proponent of enlightened absolutism and regalism.
In 1731, the 15-year-old Charles became Duke of Parma and Piacenza following the death of his childless grand-uncle Antonio Farnese. In 1734, at the age of 18, he led Spanish troops in a bold and almost entirely bloodless march down Italy to seize the Kingdom of Naples and Kingdom of Sicily and enforce the Spanish claim to their thrones. In 1738 he married the Princess Maria Amalia of Saxony, daughter of Augustus III of Poland, who was an educated, cultured woman. The couple had 13 children, eight of whom reached adulthood. They resided in Naples for 19 years. Charles gained valuable experience in his 25-year rule in Italy, so that he was well prepared as monarch of the Spanish Empire. His policies in Italy prefigured ones he would put in place in his 30-year rule of Spain.
Charles succeeded to the Spanish throne in 1759 upon the death of his childless half-brother Ferdinand VI. As king of Spain, Charles III made far-reaching reforms to increase the flow of funds to the crown and defend against foreign incursions on the empire. He facilitated trade and commerce, modernized agriculture and land tenure, and promoted science and university research. He implemented regalist policies to increase the power of the state regarding the church. During his reign, he expelled the Jesuits from the Spanish Empire and fostered the Enlightenment in Spain. Charles launched enquiries into the Iberian peninsula’s Muslim past, even after succeeding to the Spanish throne. He strengthened the Spanish army and navy.