Manuel I of Portugal
Manuel's mother was the granddaughter of King John I of Portugal, whereas his father was the second surviving son of King Edward of Portugal and the younger brother of King Afonso V of Portugal. In 1495, Manuel succeeded his first cousin, King John II of Portugal, who was also his brother-in-law, as husband to Manuel's sister, Eleanor of Viseu.
Sancho I of Portugal
Sancho was baptized with the name Martin (Martinho) since he was born on the feast day of Saint Martin of Tours. On 15 August 1170, he was knighted by his father, King Afonso I, and from then on he became his second in command, both administratively and militarily. At this time, the independence of Portugal (declared in 1139) was not firmly established. The kings of León and Castile were trying to re-annex the country and the Roman Catholic Church was late in giving its blessing and approval. Due to this situation Afonso I had to search for allies within the Iberian Peninsula. Portugal made an alliance with the Crown of Aragon and together they fought Castile and León. To secure the agreement, Sancho married Dulce, younger sister of King Alfonso II of Aragon, in 1174. Aragon was thus the first Iberian kingdom to recognize the independence of Portugal.