Frederick I

Frederick I or Friedrich I may refer to:


 * Frederick of Utrecht or Frederick I (815/16–834/38), Bishop of Utrecht.
 * Frederick I, Duke of Upper Lorraine (942–978)
 * Frederick I, Duke of Swabia (1050–1105)
 * Frederick I, Count of Zollern (died 1125)
 * Frederick I (archbishop of Cologne) (1075–1171)
 * Frederick I, Holy Roman Emperor (1122–1190), "Frederick Barbarossa"
 * Frederick I, Burgrave of Nuremberg (1139–1200)
 * Frederick I, Duke of Lorraine (1143–1206)
 * Frederick I, Count of Berg-Altena (1173–1198)
 * Frederick I, Duke of Austria (Babenberg) (1175–1198), "Frederick the Catholic"
 * Frederick I, Margrave of Baden (1249–1268)
 * Frederick I, Margrave of Meissen (1257–1323), "the Brave"
 * Frederick I of Austria (Habsburg) (1286–1330), "Frederick the Fair"
 * Frederick I, Marquess of Saluzzo (1287–1336)
 * Frederick I, Count of Celje (1300-59)
 * Frederick I, Duke of Athens (died 1355)
 * Frederick I, Elector of Saxony (1370–1428), "the Belligerent" or "the Warlike"
 * Frederick I, Elector of Brandenburg (1371–1440), also Burgrave of Nuremberg (as Frederick VI)
 * Frederick I, Count of Vaudémont (1371–1415)
 * Frederick I, Duke of Brunswick-Lüneburg (died 1400)
 * Frederick I, Count Palatine of Simmern (1417–1480), "the Hunsrücker"
 * Frederick I, Duke of Brunswick-Osterode (died 1421)
 * Frederick I, Elector Palatine (1425–1476), "the Victorious"
 * Frederick I of Mantua (1441–1484), Marquess of Mantua
 * Frederick I of Naples (1452–1504), King of Naples
 * Frederick I, Margrave of Brandenburg-Ansbach (1460–1536)
 * Frederick I of Denmark (1471–1533), King of Denmark and Norway
 * Frederick I, Duke of Württemberg (1557–1608)
 * Frederick I, Landgrave of Hesse-Homburg (1585–1638)
 * Frederick I, Duke of Saxe-Gotha-Altenburg (1646–1691)
 * Frederick I of Prussia (1657–1713), King in Prussia
 * Frederick I of Sweden (1676–1751), King of Sweden
 * Frederick I of Württemberg (1754–1816), King of Württemberg
 * Frederick I, Duke of Saxe-Altenburg (1763–1834)
 * Frederick I, Grand Duke of Baden (1826–1907)
 * Frederick I, Duke of Anhalt (1831–1904)