The Tri-County Baseball League of Western Massachusetts was born out of the Bi-County League, when, in 1929, the Merricks Athletic Association, playing out of Springfield,  was admitted into the League. The League consisted of six teams: Greenfield, Shelburne Falls, Easthampton, Northampton, Holyoke, and Merricks.         

Merricks A.A. shared League Field (later, Pynchon Park) in  Springfield, Massachusetts with the Springfield Ponies (1893- 1934) of the Eastern League. In the '30s and '40s, the Triple-A (Amateur Athletic Association) Industrial League shared players with the Tri-County League due to the Country being at war and younger players being scarce. Eventually, Spalding, Chapman Valve, and Bosch, who were playing in both Leagues, moved over to Tri-County. In the '60s the League had grown to over a dozen teams. Over the next few decades, under the leadership of Henry Palmer, followed by Kevin McGurk, the League grew to 17 teams, and ultimately splitting into American and National divisions. The American Division was comprised of teams that had been in the League for a decade, or more; PeoplesBank, bankESB, Teddy Bear Pools, DiFranco Realty, Chicopee Falls Tigers, and the St. Joseph's Saints. The National Division was a development League, rostered with young players on their way up, and veteran players looking to stay in the game.                                                                                                                                                                                                                                                                                                                                                                                                        In June of 2019, with the season in full swing, President McGurk passed away unexpectedly. The League assembled the Board and held an emergency session to find a new President. Western Mass Baseball Hall of Fame Umpire and Coach Don LaValley was unanimously voted in to succeed Kevin. In March of 2020, with President LaValley about to lead his first full season, COVID landed. In his first major move as President, Don LaValley announced that the 2020 season would be postponed.                              

As the League returned to the field in 2021, the American and National Divisions merged into one League, which maintains the current format. 

In March of 2023, President Valley announced his retirement, and Vice President Mike Kennedy ascended to the role of President. Mike had a stellar playing and coaching career in Western Massachusetts baseball and will begin his first season as President in 2023. 

 *Research was provided by author, historian, and player in the Tri-County League,  Dan Genovese, the late Garry Brown from the Springfield Republican, and Baseball-Reference publication.