[1][2] The club was founded in 1976 to serve the communities of Unionville and Milliken in Ontario.

[4] In their inaugural season, the women's team finished in 4th place.

[5] Unionville announced that their club would go with a fully professional model, as opposed to an amateur or semi-professional approach, becoming the second fully professional team in the league, after Toronto FC III.

[6] The men's team was formed through a partnership with York Region Shooters, who played in the Canadian Soccer League until 2017, to form a professional club in L1O to begin in 2018, created through the relationship of Shooters' owner Tony De Thomasis and UMSC coach Filipe Bento.

[7] They played their inaugural match on April 29, 2018 against Windsor TFC,[8] which resulted in a 3–1 victory.