"The Fat" is an epithet which may refer to:

• Albert II, Duke of Brunswick-Lüneburg (c. 1268–1318)
• Afonso II of Portugal (1185–1223), King of Portugal
• Charles the Fat (839–888), King of Alemannia, King of Italy, western Emperor (as Charles III), King of East Francia and King of West Francia
• Pope Clement IV (1190–1268), known as "Guy le Gros" (French for "Guy the Fat")
• Conan III, Duke of Brittany (c. 1093 to 1096–1148)
• Donough O'Brien, 2nd Earl of Thomond (died 1553)
• Floris II, Count of Holland (died 1121)
• Folke the Fat, reportedly the most powerful man in Sweden around 1100
• Frederick of Altmark ( c. 1424–1463), Margrave of the Brandenburg and Lord of the Altmark
• Henry I of Cyprus (1217–1253), King of Cyprus
• Henry I of Navarre (c. 1244–1274), King of Navarre and Count of Champagne and Brie (as Henry III)
• Henry V, Duke of Legnica (c. 1248–1296), also Duke of Jawor and Duke of Wroclaw
• Henry, Margrave of Frisia (c. 1055–1101), also Count in Rittigau and Eichsfeld
• Hugh d'Avranches, Earl of Chester (died 1101)
• Humbert II, Count of Savoy (1065–1103)
• James Mor Stewart (c. 1400–1429 or 1449), leader of two rebellions against King James I of Scotland
• John Komnenos the Fat, Byzantine noble who in 1200 attempted to usurp the imperial throne from Alexios III Angelos
• Juan Núñez I de Lara (died 1294), Lord of Lerma, Amaya, Dueñas, Palenzuela, Tordehumos, Torrelobatón and la Mota
• Leopold IV, Duke of Austria (1371–1411), Duke of Further Austria
• Louis VI of France (1081–1137), King of France
• Mieszko II the Fat (c. 1220–1246), Duke of Opole-Racibórz and Duke of Kalisz-Wieluń
• Olaf II of Norway (995–1030), King of Norway
• Peter II of Cyprus (c. 1354 or 1357−1382), King of Cyprus
• Ptolemy VIII Physcon (c. 182 BC–116 BC), Pharaoh of Egypt
• Reginald III, Duke of Guelders (1333–1371)
• Sancho I of León (died 966), King of León
• Welf II, Duke of Bavaria (1072–1120)
• William VI, Duke of Aquitaine (1004–1038)

See also

• List of people known as the Stout