The morning mist hung heavy over the Richelieu River as American forces moved into position around Fort St. Jean on September 17, 1775. This date marked the formal beginning of what would become a grueling 45-day siege, a pivotal engagement in the ambitious American campaign to bring Canada into the revolutionary cause against British rule. The siege of Fort St. Jean would test the resolve of untested American forces and ultimately determine whether the Continental Army could successfully prosecute its first major offensive operation beyond the thirteen colonies.