"The Cardinal King" (Fr. le Cardinal Poi, Ger. der Kardinalkönig, Por. o Cardeal Rei, Sp. el Cardenal-Rey): Henry I of Portugal
"The Cardinal Infante": Cardinal-Infante Ferdinand
"The Careless" (Cat. el Descurat): John I of Aragon
"The Carnivore" (Msaker, Fr. le Carnivore): Ashot IV, Patrician of Armenia, 806–826
"The Carpenter" (Fr. Charpentier): William, Count of Melun
"The Cartridge Prince" (Ger. Kartdtschenprinz): Wilhelm I of Germany 4
"The Castilian" (Sp. el Castellano): Alvaro, Count of Urgell, 1243–1268
"The Catholic" (Cat. el Catolic, Dut. de Katholieke, Fr. le Catholique, Ger. der Katholische, It. il Cattolico, Nor. den Katolske, Pol. Katolicki, Por. o Católico, Sp. el Catolico):
Alfonso I
Andrew I of Hungary
Ferdinand II of Aragon
Frederick I of Austria (Babenberg)
Isabella I of Castile
Peter II of Aragon
Mary I of England
"The Catholic Kings":
Ferdinand II of Aragon
Isabella of Castile
"The Caulker" (Fr. le Calfat, Gr. Kalafates, Lat. Calaphates, Por. o Calafetador): Michael V
"The Cavalier", "Mad Cavalier" (Ger. der Kavalier):
"The Christian Sultan": Frederick II, Holy Roman Emperor 14
"The Chronicler" (Fr. le Croniqueur, Sp. el Cronista):
Nithard of Ponthieu (795–844)
Pedro Lopez de Ayala (1332-1407), Lord of Ayala 15
"The Church's-Friend": Henry of Reuss-Weida (1282–1306)
"The Cicero of Germany": John Cicero, Elector of Brandenburg
"The Citizen King" (Fr. le Roi Citoyen): Louis Philippe of France
"The City's Friend": Henry I of Reuss-Lobenstein (d.1488)
"The Clatterer": Eystein Ivarsson
"The Clement" (It. il Clemente, Por. O Clemente): John VI of Portugal
"The Cleric" (Gae. Claireac): Corcran Claireach 16
"The Cloister-Founder": [[Henry I of Reuss-Weida (c.1206–1225)
"The Clubfoot" (Klumpfot): Sverker I of Sweden
"The Coachman of Europe: Klemens Wenzel von Metternich 1718
"The Coal-Burner" (Ger. Köhler, Sp. el Quemador de Carbón, Swe. Kolbränna): Anund Jacob of Sweden
"The [...] o' the North" (Coileach an taobh tuath): Alexander Gordon, 4th Duke of Gordon
"The Collector": Thomas Howard, 21st Earl of Arundel
"The Comb": Basil III of Pskov (1448–1455)
"The Competitor" was a candidate for the Scottish throne after the death of the 7-year-old Margaret of Scotland, the "Maid of Norway", in 1290.
Eric II of Norway
Floris V, Count of Holland
John of Scotland
John "the Red" Comyn
John de Hastings , 2nd Baron Hastings
Nicholas de Soules
Patrick de Dunbar, 7th Earl of Dunbar
Patrick Galithly
Robert Bruce, 5th Lord of Annandale
Robert de Pynkeney
Roger de Mandeville
William de Ros, 2nd Baron de Ros
William de Vesci, Baron de Vesci
"The Completor of the Perfect Ten": Suleiman the Magnificent 19
"The Concubine": Anne Boleyn
"The Condemned" (Ger. der Verdammte): Henry VI, Count of Luxemburg, 1281–1288
"The Confessor" (Dan. Bekenderen, Dut. de Belijder, Fr. le Confesseur, Ger. der Bekenner, Hun. Hitvalló, It. il Confessore, Nor. Bekjenneren, Pol. Wyznawca, Por. o Confessor, Sp. el Confesor, Swe. Bekännaren):
"The Conqueror" (Arabic an-Nasir, Dan. Erobreren, Dut. de Veroveraar, Fr. le Conquerant, Ger. der Eroberer, Hun. Hódító, It. il Conquistatore, Nor. Erobraren, Pol. Zdobywca, Por. o Conquistador, Sp. el Conquistador, Swe. Erövraren, Tur. el-Fatih)
"The Crooked Heir": Thomas FitzGerald, Lord of Decies (1261–1298)
"The Cunning", "Clever", "Crafty", "Weasel", "Sly", "Smart Head" (Fr. l'Adroit, Guiscard, Geo. Narin, Ger. der Verschlagene, It. il Guiscardo, Malizia, Lat. Viscardus, Pol. Zwinny, Sp. el Zurdo, Tur. Bedros):
"The Cruel", "Grave", "Harsh", "Serious", "Severe" (Cze. Kruty, Ukrutny, Dut. de Wrede, de Verschrikkelijke, Fr. le Cruel, le Severe, Ger. der Ernssthafte, der Grausame, der Freudholdige, der Kuhne, Pol. Okrutny, Surowy, Por. o Cruel, Sp. el Cruel, el Serio, el Severo, Swe. den Strange):
"Canmore" (Cenn Mór, Ceann Mór, Ceannmhor, Great Head, With the Large Head, Fr. Grosse-Tête, Pol. Wielka Głowa, Swe. med Stora Huvudet): Malcolm III of Scotland
"Capet (Lat. Capetus, wearing a capot or monk's hood): Hugh Capet of France
"Captain Luckless": James Hamilton, 1st Duke of Hamilton
