The governor worked well with frontier traders, explores, and missionaries. His term saw a great expansion in the number of western forts, the linkage of Canadian and Louisiana colonies. Exploration pushed west to the Rocky Mountains.
Despite a generally peaceful and prosperous administration, he was blamed for the fall of Fortress Louisbourg in 1745, and was recalled in 1746, returning to France to following year.
The town of Beauharnois, Quebec was named for him.