List of nicknames of European royalty and nobility: I
- Iago ab Idwal the Bald
- Iancu Sasul the Saxon
- Ibrahim I, Ottoman Sultan the Mad 1
- Ibrahim I the Turkish Caligula 2
- Ida of Bernicia the Flame-Bearer
- Ida of Boulogne the Blind 3
- Idwal Foel the Bald
- Idwal Roebuck 4
- Idwal ap Cadwaladr, Prince of North Wales (664–712) Iwrch
- Igor of Kiev the Old
- Igor II of Kiev the Brave, the Saint
- Imre Thököly the Kuruc-King 5
- Indorba Finn , wife of Eogan the Lion, King of Tyrone the White
- Inês de Castro the Beauty of Castile 6, the Heron's Neck
- Inge I of Sweden the Elder, Inge Stenkilsson (Inge, son of Stenkil), the Evilheart, the Younger
- Inge Magnusson the Baglar King
- Ingenuus the Barracks Emperor, the Emperor of the Army
- Ingibiorg Finnsdottir the Earl's Mother, wife of Malcolm III of Scotland
- Ingjald Helgasson, King of Dublin the White
- Ingjald the Ill-Ruler, the Evil-Adviser
- Ingobrand, 1st Lord of Pierrepont (c.1025–c.1090) Mastue
- Iñigo I of Pamplona Arista (Aritza, Aiza)
- Íñigo Lopez, Lord of Vizcaya "Ezquerra" 7
- Ioan Vodă cel Cumplit the Terrible
- Ioann Shvarn, Grand Duke of Lithuania, 1268–1269 "The Lightning", "Lightning Bolt"
- Iorwerth Drwyndwn ap Owain, Prince of Gwynedd the Flat-Nosed, the Broken-Nosed
- Irene (empress) Irene of Athens 8, the Athenian, the Saint
- Irene the Gypsy, wife of Petru Schiopul, Prince of Moldavia, 1582–1591
- Irene Cantacuzene the Cursed 9
- Isabeau de Hauteville, wife of Odet de Coligny, Elizabeth de Kanteville, Madame la Cardinale 10 11
- Isabel Luísa, Princess of Beira the Always-Engaged
- Isabella I of Castile the Catholic
- Isabella II of Spain the Queen of Intrigues 12, She of Sad Destinies
- Isabella of Angouleme the Helen of the Middle Ages
- Isabella of France the Fair, the She-Wolf of France
- Isabella d'Este the First Lady of the Renaissance
- Isabel Sarmiento de Zúñiga, 3rd Countess of Santa Maria de Ortiguiera la Bermeja
- Ischkhanik Artsruni (d.1042) the Little Prince, son of Khachig Artsruni, Prince of T'ornavan
- Ismail ben Zennun of Toledo al-Zafir 13
- István Dobó the Hero of Eger 14
- István Széchenyi Ignotus 15, the Greatest of All Hungarians, the Greatest of the Magyars 16 17
- István Tisza the Man of the Bible 18
- Itta the Saint
- Itta de Gascogne the Saint
- Iuga of Moldavia the Limp
- Ivailo of Bulgaria the Swineherd, the Usurper
- Ivan II of Russia the Fair, le Placide, the Debonair 19, the Beauty 20
- Ivan II, Prince of Riazan, 1326–1341 Korotopol
- Ivan II, Prince of Rostov-Borissoglebsk, 1418–? ''Dolgiy'
- Ivan III of Russia the Great, the Gatherer of the Russian Lands
- Ivan IV of Russia the Terrible 21 22 23, the Awesome, the Father of Tsarism 24, the Stalin of the Sixteenth Century 25
- Ivan VII, Grand Prince of Riazan, 1500–1521 the Exile
- Ivan, Prince of Novgorod-Severskiy, 1454–? Shemiakin
- Ivan, Prince Shuyskiy Skopa 26
- Ivan Shuiski Gorbaty 27
- Ivan of Pskov Gubka 28
- Ivan, Prince of Pereyaslavl (d.1302) Tikhiy
- Ivan, Prince of Suzdal-Nizhegorod Tugiy Luk 29
- Ivan of Torusa Tolstaia Golova 30, Tretnoy 31
- Ivan the Young the Younger
- Ivan, Prince of Starodub (d.1315) Kalistrat
- Ivan, Prince of Starodub, 1238–1247 Kasha
- Ivar of Novgorod the Glorious
- Ivan, Prince of Yaroslavl, ?–1426 the Fat
- Ivan of Obolensk Dolgoruky 32
- Ivan, Prince of Yaroslavl Bolshoy (the Big) 33
- Ivan, Prince Glazaty Barbasha 34
- Ivan Rostislavich, Prince of Halych Berladnik 35 36
- Ivan, Prince Shuyskiy Pugovka 37
- Ivan, Prince Shuyskiy Pletenj 38
- Ivan of Riazan Postnik 39
- Ivar Vidfamne Vifadme, Vidfami (Wide Fathom, Wide Reacher)
- Ivan Asen I of Bulgaria the Strong
- Ivan Asen III Mytzes
- Ivar, Jarl of the Uplands the White
- Ivar the Boneless the Boneless 40
- Izyaslav I, Prince of Riazan (1077-1096) the Younger
- "The Immortal Seven":
- Charles Talbot, 1st Duke of Shrewsbury
- Edward Russell, 1st Earl of Orford
- Henry Compton, Bishop of London
- Henry Sydney, 1st Earl of Romney
- Richard Lumley, 1st Earl of Scarbrough
- Thomas Osborne, 1st Duke of Leeds
- William Cavendish, 1st Duke of Devonshire
