1. On September 21, 1621, the Pilgrims in Plymouth, Massachusetts signed a treaty with the Wampanoag Native Americans, which became known as the first Thanksgiving.

2. The Boston Tea Party occurred on September 21, 1773, when colonists in Boston, Massachusetts dumped tea into the harbor to protest against British taxation without representation.

3. On September 21, 1860, Massachusetts Senator Charles Sumner returned to the Senate after a brutal attack by a member of the House of Representatives who disagreed with his anti-slavery views.

4. On September 21, 1938, the Great New England Hurricane struck Massachusetts, killing over 700 people and causing widespread devastation.

5. Cardinal Richard Cushing, who served as Archbishop of Boston from 1944 to 1970, was born on September 21, 1895 in South Boston, Massachusetts. He became known for his championing of religious freedom and civil rights.