Pedro Álvarez de Soutomaior, known by the sobriquet Pedro Madruga, was a Galician nobleman and knight. He was a notable figure in Galicia where he exerted certain influence in the Portuguese court, as well as spending time in that of Castile. He was one of the leading lords who suppressed the Irmandiño peasant revolts in the 1460s, and also fought in favor of the Portuguese-backed claimant to the Castilian throne, Joanna la Beltraneja, in the War of the Castilian Succession.

The Irmandiño revolts were two revolts that took place in the 15th-century Kingdom of Galicia against attempts by the regional nobility to maintain their rights over the peasantry and bourgeoisie. The revolts were also part of the larger phenomenon of popular revolts in late medieval Europe caused by the general economic and demographic crises in Europe during the 14th and 15th centuries. Similar rebellions broke out in the Hispanic Kingdoms, including the War of the Remences in Catalonia and the foráneo revolts in the Balearic Islands.