O’Connor, Rory. c1116-98. Last high king of Ireland 1166-75. Submitted to Henry II in Treaty of Windsor.

October Revolution. 1917. Bolsheviks, Lenin and Trotsky overthrow Kerensky’s Socialist provisional government in Russian Revolution.

Odeon. Athenian place of music and poetry competition. Parisian theater 1728.

Odin. King of Scandinavian gods who holds court in Valhalla.

OECD. Organisation for Economic Cooperation and Development. 1961. For expansion of world trade. OEEC + US, Canada, Australia, NZ.

Oedipus. Solved the riddle of the sphynx. Killed his father and married his mother.

Offa. 755-796. King of Mercia 757-. Founded St. Alban’s abbey. Dee Dyke vs Welsh 785. Introduced coinage. Treaty with Charlemagne. Began unification of England.

Ogadai. 1185-1241. Mongol ruler 1229-41. Conquered China to Poland, Hungary.

Olaf V. 1903-91 King of Norway 1957-. Commanded army vs Germany in 1944, then fled to England.

Old Catholics. 1870. Catholic sect vs papal infallibility. Joined Church of England 1931.

Old English. 5-11C. Teutonic language of England.

Olympias. c175-316BC. Wife of Philip of Macedonia. Mother of Alexander the Great.

Oñate, Juan de. -1630. Spanish explorer of southwest US.

O’Neill, Shane. c1530-67. Irish chief rebelled vs England, slain by rival clan.

Orange, House of. French dynasty influential in Netherlands. William I. William III.

Oranges, War of. 1801. France and Spain defeat and divide Portugal.

Orcagna, Andrea. 1308-68. Florentine painter and sculptor.

Orcus. Roman god of underworld and dead. = Hades.

Orestes. Electra’s brother. Killed mother and her lover to avenge death of his father, Agamemnon.

Origen. c185-254. Alexandrian. Sought to justify Christianity in terms of Greek philosophy. On First Principles.

Orlando, Vittorio. 1860-1952. Italian Prime Minister 1917-19. Versailles negotiator.

Orléanists. 1830-48. French supporters of Louis-Philippe vs republicans and Bonapartists.

Orléans. 1344-. Branch of French Valois and Bourbons.

Orléans, Philippe II, duc d’. 1674-1723. French soldier Wars of Grand Alliance, Spanish Succession. Regent for Louis XV.

Orwell, George. 1903-50. English satirical novelist and social critic: Animal Farm 1945, 1984 1948.

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