The Middlesex census division, which consists of the county together with the City of London and three First Nations reserves, had a population of 500,563 in 2021.

Simcoe toured the southwestern portion of the province's territory in early 1793 and concluded that the lower forks of the Thames would be best suited as the future site of the provincial capital.

[citation needed] Suffolk County was reorganized as Middlesex County, as part of the London District, in 1798 by the Legislative Assembly of Upper Canada,[4] consisting of the townships of London, Westminster, Dorchester, Yarmouth, Southwold, Dunwich, Aldborough and Delaware.

[9] Upon the abolition of the London District in January 1850, Middlesex County was constituted for municipal purposes.

[13] There was a village at Ekfrid Station that had a blacksmith's shop, a gristmill and a store that was created by the Grand Truck railroad.

[14] Today it is ghost town as the post office closed on 31 January 1914 and the railroad station in 1950.