Duke of Frías
Fernández de Velasco was the son of Íñigo Fernández de Velasco, 2nd Duke of Frías and of Doña María de Tovar, Lady of Berlanga. He married his cousin Doña Juliana de Velasco y Aragón, 1st Countess of Castilnovo, daughter of Bernardino Fernández de Velasco, 1st Duke of Frías in 1508, but they had no issue. He succeeded as 3rd Duke of Frias in 1528.