1215 – King John of England put his seal on the Magna Carta.

1381 – The Peasants’ Revolt led by Wat Tyler was crushed in London.

1667 – The first successful blood transfusion was performed by Dr. Jean-Baptiste Denys.

1752 – Benjamin Franklin proved that lightning is electricity.

1775 – George Washington was appointed commander-in-chief of the Continental Army.

1804 – The Twelfth Amendment to the United States Constitution was ratified, reforming the Electoral College.

1846 – The Oregon Treaty was signed between the United States and Britain, settling the boundary dispute.

1904 – The steamship General Slocum caught fire and sank in New York City’s East River, killing over 1,000 people.

1924 – Native Americans were granted U.S. citizenship.

1991 – Mount Pinatubo erupted in the Philippines, causing widespread devastation.