April 19

The Kishinev pogrom began in the Bessarabian capital; the violence drew worldwide attention and spurred Jewish emigration and self-defense efforts.

The Warsaw Ghetto Uprising began as fighters of the Jewish Combat Organization resisted the deportation of the ghetto's remaining inhabitants.

Philipp Melanchthon, the Reformation's first systematic theologian and principal author of the Augsburg Confession, died at Wittenberg.

The conclave elected Cardinal Joseph Ratzinger as pope; he took the name Benedict XVI, succeeding John Paul II.