King Denis of Portugal, also known as Denis I, reigned from 1279 to 1325. He was the son of Afonso III and is often referred to as "the Farmer King" due to his promotion of agriculture and land cultivation. Denis established the first Portuguese university in Lisbon, which contributed to the growth of education in the country. During his reign, Denis worked to strengthen the monarchy and improve the economy. He implemented various reforms, including the creation of a legal code and the promotion of trade. His efforts helped to stabilize Portugal and laid the groundwork for future development.