Prince of Portugal (Portuguese: PrÃncipe de Portugal), officially Hereditary Prince of Portugal (PrÃncipe Herdeiro de Portugal), was the title held by the heir-apparent to the Kingdom of Portugal, from 1433 to 1645.
The title differs from the title Infante of Portugal, which is the title given to all children of the monarch except the heir, and is often translated into English as "prince".
History
Due to English tradition introduced to the Portuguese court by Philippa of Lancaster, her son Edward I of Portugal sought to create a princely title for the heir-apparent, much like the Prince of Wales, to distinguish him from his siblings, who were Infantes of Portugal. Until that time, the heir to the throne was also titled Infante.
In 1433 Edward created his eldest son, the future Afonso V of Portugal, Prince of Portugal. The monarchies of Castile, Aragon and England already had princely titles for their heirs-apparent and now Portugal had one, so that foreign powers would not underestimate the prestige of the Kingdom
In 1645, the title was replaced with Prince of Brazil.