The Chester County Coed Softball League had a modest beginning in 1978, when employees from Hamilton Bank in Exton, Pa. challenged employees from Roy F. Weston, Inc. in West Chester, Pa. to a softball game. This first game was played on Ashbridge Field just outside of West Chester, Pa. on ground owned by Thomas Burneson. In 1979, four teams joined Hamilton Bank and Roy F. Weston to create a six-team league. The following year, the league expanded to ten teams that were all aligned within one large division. Many of the early games were played on Ashbridge Field, the former Embryville State Hospital grounds near Marshallton, Pa., Schramm's Field adjacent to West Chester Henderson High School in West Chester, Pa., and the Borough of West Chester's Green Field near West Chester University. At this time, formal rules were established and distributed to the various managers and their associated teams. The most significant rule was that each team had to play three women at all times both in the field and in the batting rotation. Other established rules included a six to twelve foot pitch arc, a line-up consisting of a minimum of eight players, and a 15-run mercy rule after five innings. Members of each participating team umpired games, with the home plate umpire usually provided by the home team

By the early 1990's, the Chester County Coed Softball League had moved the majority of its games to West Chester, Pa. in order to be centrally located in the county. Once in West Chester, many of the West Chester Area School District athletic fields, including those at East High School, Henderson High School, Stetson Middle School, Exton Elementary, Fern Hill Elementary, and Mary C. House Elementary were heavily utilized. In addition, league games continued to be played at Green Field (West Chester Borough) and now at Hallowell Field behind the West Goshen Township Municipal Building. Games were also played on one athletic field at Downingtown High School in Downingtown, Pa. The Chester County Coed Softball League was also a charter member of the newly established West Chester Area Sports Association. This organization was formed primarily to construct a sports complex at the intersection of Route 202 and Westtown Road in West Goshen Township. Two state of the art softball fields were built at the complex and were used by Chester County Coed Softball League along with other leagues for spring, summer, and fall softball play. The number of teams continued to increase throughout the 1990's until the size of the league leveled off at sixteen teams. Four divisions of four teams each were established creating rivalries within each division. At this time, the top two teams from each division qualified for the playoffs that consisted of a best of three series for the quarter and semi finals and a best of five series for the championship. Amateur Softball Association umpires were hired to establish more consistency and professionalism in play calling for both regular season and playoff games.

In 2007, the Spring League jumped to 26 teams in two classified divisions and the Fall League topped off at 18 teams resulting in an all-time high of over 500 participants for the year.

Ed Weiss of Hamilton Bank / First National Bank (1978 – 1988), Jamie McVickar of West Chester Electric (1989 – 1990), and Ken Joire' of John Milner Associates / John Milner Architects / Trego's Automotive (1991 – 2005) have served as past league presidents.