April 17:

A.D. 1492: Christopher Columbo signs a contract with Spain to find the Indies by sailing west.

A.D. 1534: St. Sir Thomas More is imprisoned in the Tower of London.

A.D. 1793: The Battle of Warsaw.

A.D. 1939: Joseph Stalin signs an anti-Nazi pact with the British and French.

April 18:

A.D. 310: St. Eusebius begins his reign as Bishop of Rome.

A.D. 1506: The cornerstone of the current St. Peter's Basilica is laid.

A.D. 1521: Martin Luther is questioned by Cardinal Alexander in the Diet of Worms.

A.D. 1775: Paul Revere and William Dawes ride from Charleston to Lexington, warning the advance of the British, which is the beginning of the American Revolution.

A.D. 1783: Fighting ceases in the American Revolution after exactly eight years.