The township comprises the communities of Avonry, Babys Point, Becher, Bickford, Bradshaw, Brigden, Charlemont, Colinville, Courtright, Corunna, Cromar, Duthill, Frog Point, Froomfield, Kimball, Ladysmith, Moore Centre, Mooretown, Osborne, Payne, Port Lambton, Seckerton, Sombra, Sykeston, Thornyhurst, Vye's Grove, Waubuno, West Becher, Wilkesport.

Early maps show the typical colonial French lots, with narrow frontage along the river.

The town's name indirectly honors Beresford's commander in that battle, Sir John Moore (general), who was mortally wounded at Corunna, Spain, in a fight with French forces as the English tried to embark on their ships for retreat to Great Britain.

[citation needed] Corunna was not chosen for the new capital, as it was considered vulnerable due to being too close to the Canada–US border.

In the 1820s–1830s, the prospect of an Irish Fenian raid from the United States was considered a serious threat to the British colonies.

Today, a small stone cairn stands along Baird Street, near the CSX north-south train track that divides the town.

The dimensions of these streets that now make up the downtown: Beckwith, Beresford, Baird, Fane, Paget, Lyndoch, Cameron, Bentinck, Colborne, Hill, Murray, etc., follow some of the original specifications set out by Beresford's survey crew as part of the plans to create a capital.

One early settler was James Cruickshank, who settled in 1834 south of Corunna on the Eighth Line near Kimball Side Road.

A plaque to commemorate his early contribution to the township was installed in a Corunna park on Beresford Street, on land donated by his descendants.

Entrepreneurs wanted to build a canal through Corunna, but it was abandoned soon after construction, as operators could not maintain consistent water levels.

A general store was on the west side of Lyndoch, north of Hill, where an Esso station later stood.

Its wooden structure is bolstered by enormous trunks of the area's original trees, which were squared off and put in place to build the church.

Kayla Baby owned all the land from this point, and all of Port Lambton site, which he inherited from his grandfather in 1742.

The First Nations people, long the original inhabitants of all this area, were prevented by the Province from selling their land without official approval.

[3] St. Clair receives 97 centimetres (38.2 in) and since it is not located in the snowbelt region, snow cover is intermittent throughout the season.

The building currently housing Colonel Cameron was previously Father Gerald LaBelle Catholic School, which was open between 1976 and the early 2000s.