Alfonso d'Avalos d'Aquino, 4th Marchese di Pescara e del Vasto (1502 – March 31, 1546) was a condottiero of Spanish-Italian origin.
He was born in Ischia, the nephew of Francesco Ferdinando I d´Ávalos, inheriting his uncle titles after 1525, fighting the French and the Venetians by his side. During the period 1526 - 1528, he fought under Hugo of Moncada, being captured in 1528 by the Genoese admiral Andrea Doria.
In July 1535 he was part of the naval troops reconquering the city of Tunis in North Africa. The failure on the third war against France trying to invade Provence, and the death of the first Governor of the Duchy of Milan, Antonio de Leyva, prompted him, in 1538, to accept the nomination as governor, replacing Marino Caracciolo, the second governor, becoming some sort of protector of literary and musical people. Wars with French and North Italians ended for a while with the Treaty of Crespy (1544). He also became a Knight in the Order of the Golden Fleece.
Having fought at the Battle of Pavia, he later represented Spain as Ambassador, in 1538, on the succession to the new Doge of the Republic of Venice, Pietro Lando.
He commanded the Imperial army in Italy during the Italian War of 1542 and was defeated by the French at the Battle of Ceresole. However, in the Battle of Serravalle, June 2, 1544, an aftermath of the Italian War of 1542, he managed to defeat a force of freshly raised Italian mercenaries in French service, commanded by Pietro Strozzi and Giovanni Francesco Orsini, Count of Pitigliano.
He married in 1523 with Maria d'Aragona and had 5 children including
| Preceded by Cardinal Marino Caracciolo |
Governors of the Duchy of Milan 1538–1546 |
Succeeded by Ferrante Gonzaga |