Prince Miguel of Braganza, Duke of Viseu (Portuguese: Príncipe Miguel de Bragança, Duque de Viseu; 22 September 1878 – 21 February 1923) was a member of the exiled branch of the House of Braganza. The eldest son of the Miguelist pretender to the throne of Portugal he married an American heiress in 1909 and in 1920 renounced his rights to the throne. His full given names were Miguel Maximiliano Sebastião Maria.

Miguel was born in Reichenau an der Rax, Austria-Hungary the eldest son and heir of the Miguelist pretender to the Portuguese throne Miguel, Duke of Braganza and his first wife Princess Elisabeth of Thurn and Taxis. Prince Miguel's father was the head of the non reigning branch of the Portuguese Royal House that had been exiled from Portugal. The exile was the result of the Portuguese law of banishment of 1834 and the constitution of 1838 which was brought about because in 1828 his grandfather Miguel usurped the throne of Portugal from his niece Queen Maria II. His grandfather reigned as king until 1834 when Maria II was restored.

Duke of Viseu (in Portuguese Duque de Viseu) was a Portuguese Royal Dukedom created in 1415 by King John I of Portugal for his third male child, Prince Henry the Navigator, following the conquest of Ceuta.

When Prince Henry the Navigator died without issue, his nephew, Infante Ferdinand of Portugal (King Edward of Portugal's younger son), who was already Duke of Beja, inherited the Dukedom of Viseu and, when his younger son became King of Portugal as Manuel I, this became a royal Dukedom.

Viseu (Portuguese pronunciation: [viˈzew]) is both a city (capital of Viseu District) and a municipality in the Dão-Lafões Subregion of Centro Region, Portugal. The municipality, with an area of 507.1 km², has a population of 99,593 (2011), and the city proper has around 53,000. The Greater Metropolitan Area of Viseu is also one of the Grandes Áreas Metropolitanas - Greater Metropolitan Areas of Portugal with 354,162 inhabitants.

Viseu has undergone a considerable economic growth, especially in the areas of telecommunications, industry, trade and education. Located in Portugal's northern-center the city is a crossroads linking the seaport of Aveiro in the Atlantic coast to Guarda near the Portuguese-Spanish border and then on to Salamanca, Spain. Coimbra, the regional seat of Centro Region, is about 80 km southwest. The city is noted on the arts scene due to the Grão Vasco Museum and the Teatro Viriato. Wine making (Dao wines) is an important activity in the region. In ancient Portuguese history, Viseu is noted as one of the major urban centers in the area where Viriathus, a legendary warrior and national hero, lived. With three higher education institutions within its limits, the city has played a role as a regional educational center. Its business community is among the largest of Portugal's interior countryside.