 In 1821 , Francis C. Lowell 's business associates , looking to expand the Waltham textile operations , purchased land around the Pawtucket Falls on the Merrimack River in East Chelmsford , Massachusetts . Incorporated as the Town of Lowell in 1826 , by 1840 , the textile mills employed almost 8 @,@ 000 workers — mostly women between the ages of 16 and 35 . 
