Shelburne County was founded in 1784 shortly following the influx of Loyalist settlers evacuated from the newly independent United States.

It was originally named Port Roseway, until it became a very busy town and was considered to be the capital of Nova Scotia, in which the name was changed to Shelburne in an attempt to please Lord Shelburne, the British Prime Minister from 1782 to 1783.

The boundaries of Shelburne County were established by Governor and Council on December 16, 1785.

The area had previously been settled by French-speaking Catholic Acadians, many of whom had been deported to British Colonies.

The new arrivals included Black Loyalists who were given substandard land, particularly around Birchtown.