On This Day: April 19th

The French army captures the town of Cambrai held by Spanish troops.

In Ireland, O'Doherty's Rebellion is launched by the Burning of Derry.

England and France sign an alliance against Spain in the treaty of Blois.

The Treaty of Frankfurt between Protestants and the Holy Roman Emperor is signed.

Beginning of the Protestant Reformation: After the Second Diet of Speyer bans Lutheranism, a group of rulers (German: Fürst) and independent cities protest the reinstatement of the Edict of Worms.

The Lisbon Massacre begins, in which about two thousand Jews who had been forcibly converted to Christianity are slaughtered by Portuguese Catholics.

Following the attempt of Byzantine Emperor Michael V Kalaphates to depose his wife and empress Zoe Porphyrogenita, a popular uprising in Constantinople breaks out with the intention to restore her.

Election of Pope John XIX following the death of his brother Pope Benedict VIII.

Battle of Callinicum: A Byzantine army under Belisarius is defeated by the Persians at Raqqa (northern Syria).

The freedman Milichus betrays Piso's plot to kill the Emperor Nero and all of the conspirators are arrested.