D. Luís Filipe, Prince Royal of Portugal, Duke of Braganza, (; 21 March 1887 – 1 February 1908) was the eldest son and heir-apparent of King
Carlos I of Portugal. He was born in 1887 while his father was still
Prince Royal of Portugal, and received the usual style of the heirs to the heir of the Portuguese crown: he was then at birth 4th
Prince of Beira, with the subsidiary title of 14th
Duke of Barcelos. After his grandfather king Dom
Luís I of Portugal died, he became
Prince Royal of Portugal, with the subsidiary titles of 21st
Duke of Braganza, 20th Marquis of Vila Viçosa, 28th count of Barcelos, 25th count of Ourém, 23rd count of Arraiolos, 22nd count of Neiva; he was later created Knight Commander of the
Order of the Immaculate Conception of Vila Viçosa, Knight of the
Order of the Garter, and Knight of the
Order of the Golden Fleece.