The Columbia Encyclopedia, Sixth Edition. 2001-07.
Duarte, king of Portugal
(dwär´t) (KEY) , 13911438, king of Portugal (143338), eldest of the five sons of John I. He was a philosopher-king, notable for his legal reforms and as the author of O leal conselheiro [the loyal counselor]. Much concerned with exploration, he spurred on his brother Prince Henry the Navigator with encouragement and financial aid. The disastrous defeat (1437) of Henrys expedition against Tangier was the major event of Duartes reign.