1170 On this day in history birth of isabelle of Hainaut, queen of France (d. 1190)
1185 King Afonso II of Portugal (d. 1223) was born on April - 23.
1464 On this day in history birth of johanna van Valois, Queen of France
1464 Robert Fayrfax, composer was born on April - 23.
1484 On this day in history birth of julius Caesar Scaliger, Italy, scholar (On the Subtlety of Things)
1500 On April - 23 birth of alexander Alesius, [Aless/Alane], System theologist/physician
1500 Alexander Ales, Scottish theologian (d. 1565) was born on April - 23.
1516 Georg Fabricius, German poet, historian, and archaeologist (d. 1571) was born on April - 23.
0034 On April - 23 death of christ, crucified, according to Isaac Newton
0303 On April - 23 death of george, knight/saint/patron of England, beheaded
0725 Death of Wihtred, King of Kent on April - 23.
0871 On this day in history ethelred I, king of Wessex/brother of Alfred the Great, dies
0990 On April - 23 ekkehart II, [Palatinus], monk to St-Gallen/poet, dies
0997 Vojtech "Adalbert" of Prague, 2nd bishop of Prague/apostle, dies at 40 on this day in history.
1014 On this day in history brian Boru, king of Ireland, dies in battle at 87
1016 On April - 23 aethelbred II "the Unready", king of England (979-1016), dies