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.
Portuguese nobility
By the time of the reign of Manuel I of Portugal (1495-1521), for example, when they were appointed captains of the fleet of Pedro Álvares Cabral, who arrived in Brazil on April 22, 1500, the Portuguese nobility already had registers dating back to the 12th century. The noble members of Cabral's fleet followed this feature, since most descended from families of Castile and León, who had settled in Portugal, who had already rendered several generations of service. The few exceptions - such as Bartolomeu Dias, who received his rank and arms which he transmitted to his descendants - show the importance attributed at this period to the discoveries made.
It was also the reign of King Manuel I that rules were established that define the use of the degrees of nobility (hereditary titles), and the use of heraldic arms, preventing abuses in the adoption of both and establishing the rights of the nobility. The nobles were subject to the king and were arranged in two orders, each with three degrees:
All nobles were considered vassals of the King of Portugal. To rise in status, a noble was expected to demonstrate loyalty and service to the king.