In its early days, the village developed out of local transport and agricultural trade via rail and ship and evolved mainly into a summer resort community, serving seasonal residences and summer cottagers through much of its history.

[1] The village is now home to mostly permanent residences and commuters supported by larger cities and towns such as Sarnia, Corunna, and Wallaceburg.

Sombra was named by Sir Peregrine Maitland, the lieutenant governor of Upper Canada because it was so densely wooded that the sun was blocked out.

[2] Sombra also was a stop along the Underground Railroad en route to Owen Sound, Ontario.

[3] During the United States Prohibition in 1920s, alcohol was smuggled into across the border from Canada via the St. Clair River and Sombra was a key location for the activity.