Zoe and her sister Theodora are made sole empresses by the populace, but after two months Zoe, though 60 years old, takes for her third husband Constantine X., who succeeds 1042 The Turks invade the Roman empire 1050 After the death of Constantine, Theodora recovers the sovereignty, and, 19 months after, adopts, as her successor, Michael VI., surnamed Stratioticus 1054 Isaac Commenus I. chosen emperor by the soldiers 1057 Isaac abdicates, and when his brother refuses to succeed him, he appoints his friend Constantine XI., surnamed Ducas 1059 Jerusalem conquered by the Turks from the Saracens 1065 The crown of England is transferred from the head of Harold by the battle of Hastings, October the 14th, to William the Conqueror, duke of Normandy 1066 On the death of Ducas, his wife Eudocia, instead of protecting his three sons, Michael, Andronicus, and Constantine, usurps the sovereignty, and marries Romanus III., surnamed Diogenes 1067 Romanus being taken prisoner by the Turks, the three young princes ascend the throne, under the name of Michael Parapinaces VII., Andronicus I., and Constantine XII. 1071 The general Nicephorus Botaniates III. assumes the purple 1078 Doomsday-book begun to be compiled from a general survey of the estates of England, and finished in six years 1080 Alexius Commenus I. nephew of Isaac I. ascends the throne. His reign is rendered illustrious by the pen of his daughter, the princess Anna Commena. The Normans, under Robert of Apulia, invade the eastern empire 1081 Asia Minor finally conquered by the Turks 1084 Accession of William II. to the English throne 1087 The first crusade 1096 Jerusalem taken by the crusaders 15th July. The only learned men of this century were Avicenna, Guy d’Arezzo, Glaber, Hermannus, Franco, Peter Damiani, Michael Celularius, George Cedrenus, Berenger, Psellus, Marianus Scotus, Arzachel, William of Spires, Suidas, Peter the Hermit, Sigebert 1099 Henry I. succeeds to the throne of England 1100 Learning revived at Cambridge 1110 John, or Calojohannes, son of Alexius, succeeds at Constantinople 1118 Order of Knights Templars instituted 1118 Accession of Stephen to the English crown 1135 Manuel son of John succeeds at Constantinople 1143 The second crusade 1147 The canon law composed by Gratian, after 24 years’ labour 1151