Juan Vélaz de Medrano IV

Juan Vélaz de Medrano (c. 1382? – c. 1440s) was a prominent Navarrese nobleman, military commander, and court official who held the titles of baron and lord of Igúzquiza, Arguiñano, Arzoz, Artazu, Zabal, and Orendáin, and became the first lord of Learza in the Kingdom of Navarre. A leading ricohombre of his time, Juan served as a knight of the Kingdom, alcaide of the castles of Monjardín and Viana, and was appointed royal chamberlain to King Charles III of Navarre in 1414 and to King John II of Aragon and Navarre in 1432. In 1433, he undertook a royal pilgrimage to the Cathedral-Basilica of Our Lady of the Pillar alongside Queen Blanche I of Navarre. As head of the House of Vélaz de Medrano, Juan established the mayorazgo of Vélaz de Medrano in 1437—the oldest known hereditary mayorazgo in Viana, securing his family's legacy in Navarrese nobility.

Juan Vélaz de Medrano played an active role in several major conflicts of his time, including the Hundred Years' War during the War of Languedoc (1412) and the Aragonese civil war of 1412. He also successfully defended the city of Viana against Castilian forces in 1429–1430. Earlier, in 1410, he was the target of a local rebellion within his own fiefdom of Orendáin. His legacy of Navarrese loyalty continued through his grandsons, Juan Vélaz de Medrano y Echauz and Jaime Vélaz de Medrano y Echauz, who were prominent leaders in the defense of Navarre against the Castilian conquest, particularly during the critical years of 1512 and 1522.