Infante

Infante is a title given to children of the reigning King of Spain. It has also historically been used by Portuguese monarchs before the country became a republic. As it is a title usually used by the children of monarchs, the style of Royal Highness is also used. The female version of the word is Infanta. Fully the style is usually:

His Royal Highness The Infante Don [name] of Spain/Portugal, or
Her Royal Highness The Infanta Dona [name] of Spain/Portugal.

Examples of use in Spain

His Royal Highness The Infante Juan Carlos of Spain. Used the title before becoming King.
His Royal Highness The Infante Don Luis of Spain. Again used the title before becoming King. He was also known as The Prince of Asturias.
Her Royal Highness The Infanta Dona Mariana Victoria of Spain.

Examples of use in Portugal

Her Royal Highness Dona Maria Bárbara de Bragança, Infanta of Portugal. She later became Queen of Spain through marriage.

Infante Media

Heraldic crown of a Spanish infante
Coronet of a Portuguese infante

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