The Town was named in honour of the Duke Of Sussex, son of King George III. The area was settled by a few families before the arrival of the United Empire Loyalists in 1784 from New Jersey. As the settlement of the Loyalists developed, the Parish Of Sussex was established in 1786. Growth continued in the Parish with the development of the agricultural and forestry industry and the opening of the European and American railway line in 1860, thus leading to the incorporation of the Town Of Sussex in 1904.

The Town Of Sussex has and continues to provide services for the needs of the agricultural and forestry sector throughout the years. In addition, from 1939 through the 60's, Sussex was the location of Camp Sussex. During the war years, Camp Sussex was home to 10,000 troops, thus providing a natural tie with the Canadian Armed Forces.

Today Sussex continues to provide regional services that include health care, education, business, industry and recreation to the rural areas.