Diego Messía Felípez de Guzmán y Dávila, known as Don Diego Felippez de Guzmán (Milan, approximately 1537 - February 16, 1655), was a Spanish general and politician. From 1635, he served as Captain General and Governor of the Duchy of Milan. He fought in the Netherlands under Albert of Austria and returned to Spain, where he became an influential figure at court under the patronage of his cousin, the Duke of Olivares.
Appointed a member of the Council of State in 1626 and Marquis of Leganés in 1627, he married Polixena Spinola, a wealthy Italian heiress. He participated in the Union of Arms in the Spanish Netherlands and played a key role in the Franco-Spanish War and the Piedmontese Civil War. He defeated Odoardo Farnese and organized the Citizen Militia of Milan. In 1645, he was rehabilitated and appointed Viceroy of Catalonia, defending Lleida in 1646. He died in 1655, while serving as President of the Royal Council of Italy in Milan. In addition to his military and political career, Leganés was a prominent art collector, with a collection specialized in paintings that included 1,330 works. He was portrayed by Antoon van Dyck, whose painting is housed in the Banco Santander Foundation in Madrid.