Infante Henry, Duke of Viseu (Porto, 4 March 1394 – Sagres, 13 November 1460), better known as Henry the Navigator, is an important figure in the early days of the Portuguese Empire and the Age of Discoveries in total.

He is responsible for the early development of European exploration and maritime trade with other continents.

Henry is the third child of King John I of Portugal, founder of the Aviz dynasty, and of Philippa of Lancaster, John of Gaunt's daughter.

Henry encourages his father to conquer Ceuta (1415), the Muslim port on the North African coast across the Straits of Gibraltar from the Iberian peninsula.

He learns of the opportunities from the Saharan trade routes that terminate there, and becomes fascinated with Africa in general; he is most intrigued by the Christian legend of Prester John and the expansion of Portuguese trade.

Henry is regarded as the patron of Portuguese exploration.

In "Crónica da Guiné" Henry is described as having no luxuries, not avaricious, speaking with soft words and calm gestures, a man of many virtues who never allowed any poor person leave his presence empty-handed.