During 1776, forces under his command repulsed a British attempt to capture Charleston, which boosted his standing with the army and Congress.
It was forced to surrender in 1780 when the British captured Charleston.
Despite his lack of faith in the monitors, Du Pont did not propose any alternative plans to capture Charleston.
This was part of the second Union attempt to capture Charleston.
After the British captured Charleston in 1780, he was held as a prisoner at St. Augustine, Florida for a time.
There he practiced medicine until, in 1780, the British also captured Charleston.
In 1780 the British captured Charleston, South Carolina, and with it most of the colony's civil government and military forces.
The Legion as a whole was part of the British force that besieged and captured Charleston in 1780.
When British troops captured Charleston in 1779, the state legislature elected Rutledge governor and handed him virtually absolute power.
In April, he participated in an unsuccessful expedition to capture Charleston, South Carolina.