1240:

Battle of the Neva

Because of recent Mongol incursions into Russia, Earl Birger of the Swedes calculated that Novgorod would lack military support from other Russian cities. He landed a force at the mouth of the Neva river in an attempt to block Novgorod's access to the Baltic Sea. Prince Alexander Yaroslavich led an army against the Swedes and destroyed most of the army, a victory for which he was given the name Alexander Nevsky.

1410:

Battle of Tannenberg

Also called the Battle of Grünfelde or Grunwald, this encounter in northeastern Poland was a major victory over the Teutonic Knights, marking the beginning of its decline in power.

1274:

Saint Bonaventure

A leading theologian of his time, author, and minister of the Franciscan order, Bonaventure was declared a Doctor of the Church in the sixteenth century.

1291:

Rudolf I