Wilmington is a town in Middlesex County, Massachusetts, United States. Its population was 23,349 at the 2020 United States census. Wilmington was first settled in 1665 and was officially incorporated in 1730, from parts of Woburn, Reading, and Billerica. The first settlers are believed to have been Will Butter, Richard Harnden or Abraham Jaquith. Butter, a Sco…Wilmington is a town in Middlesex County, Massachusetts, United States. Its population was 23,349 at the 2020 United States census. Wilmington was first settled in 1665 and was officially incorporated in 1730, from parts of Woburn, Reading, and Billerica. The first settlers are believed to have been Will Butter, Richard Harnden or Abraham Jaquith. Butter, a Scottish Covenanter who fought against Cromwell in the English Civil Wars, was brought to Woburn as an indentured captive. He achieved his freedom, as did all indentured service, after nine years, then relocated to the opposite side of a large swamp in what is now Wilmington. Harnden settled in Reading, in an area that is now part of Wilmington. Jaquith settled in an area of Billerica that became part of Wilmington in 1740.