The SOMBILLA was founded in the summer of 1979. The creation of a summer Strat-O league was the idea of Tsuan in June 1979 and through the organizational, scheduling, and recruiting efforts of both Tsuan and Arnie, the league had its humble beginnings. That summer, the 'founding fathers', Tsuan, Arnie, Jed, Joel, Tom, and Eric (all Framingham, Mass. residents) were all on break from college. The six gathered in Tsuan's parents' basement and drafted team-by-team from the 1978 cards (4 teams each). After the draft, but before the games began, Eric went to live in a cabin in the New Hampshire woods, and his team was taken over by John. The 6-team league played a 50 game season. The league name 'SOMBILLA' (Strat-O-Matic Baseball Ivy League League - Advanced) was coined by Arnie at the league's second week of games, and was based on the fact that the 6 members were all then attending Ivy League schools - Harvard (Jed), Yale (Tsuan), Princeton (John), Cornell (Tom) and Penn (Arnie & Joel). That year, the SOMBILLA was considered nothing more than a one-shot deal. When the season ended (Tsuan defeating Jed in the first World Series 4-2), everyone returned to school and the SOMBILLA was history.

The idea to revive the league was Arnie's in the fall of 1981 when all of the original founders had returned to Boston to work following graduation (Tom declining to join, being replaced by one 'Lou'). That season, '81-82, marked the first season of the SOMBILLA's current winter format, a format which has lasted for every winter since. Andrew and Robin joined the league for the '82-83 season. Beginning with that season, Tsuan ceased to manage his own team, first sharing a team with Robin, then taking a year off in '83-84, and finally in '84-85 began a co-ownership with Andrew. The first 5 years of the league were the same format - 6 teams, 50 games, each team drafting 4 major league teams to form an all-star team.

At a special league meeting on October 6, 1985, the league decided to expand to 8 teams and 56 games, adding Matt and Yitz, and to become a 'permanent league' (as opposed to starting anew each season as had been the practice). Also at this meeting, Arnie was elected to a 10-year term as the league's first Commissioner. On November 17, 1985, the league held the 35-round permanent league dispersal draft. Dave joined the league for the '87-88 season, sharing Yitz's team. In '88-89, founding father Joel (Jed's roommate at the time), left the league (as did Yitz) and Dave took over Joel's team as sole owner. Yitz & Dave's former team was taken over by two new league members, Harold and Durga. In '90-91, Clint joined the league, sharing a team with Dave, moving to a co-ownership with Jed in '91-92. In 1992, the league expanded to 9 teams, by giving Land his own franchise. Land had joined the league in '91-92 by sharing a team with Dave. In 1994, Jeff joined the league, sharing a team with Dave. In 1995, Randy joined the league, taking over the managerial duties of Future Wax from Andrew, who moved to California. Also in 1995, Arni's original 10-year term as Commissioner came to a close, and he resigned as Commissioner. Dave was unanimously elected the new Commissioner. In 1996, Brian joined the league, sharing a team with Land, who moved to South Carolina to attend grad school.

In March of 1997, Dave resigned from the league, and at the league's annual meeting and draft, Arni was re-elected as Commissioner of the SOMBILLA for another 10 years. Matt was elected as the league's Vice-Commissioner.  Also in '97, Jed moved to Maryland and CLint took over the day to day managerial duties of the franchise.

In 1998, Tom joined the league, taking over managing Constantinople for Brian, who left the league.   The league returned to its Ivy League roots with Tom,  a Princeton graduate.

After the 2002 season, Clint resigned from the league.  Rather than find a replacement manager, the SOMBILLA decided to contract back to 8 teams.  The main reason was to reduce the number of series people had to play during the course of the saeson from 16 to 14.  With all of us firmly ensconsed in middle age, it was a way to reduce the time commitment, while maintaining the traditional 56 game schedule.  Jed, the out-of town GM for the doomed BiG DiG franchise, became the GM for the Manila Folders, teaming up with Matt.  The 2002 draft was not only a free/agent rookie draft, but also included players contracted out of a job.

After the 2006 season, long-time league member Matt announced his resignation from the Manila Folders.  He was replaced as Vice Commissioner by Tom.  It was not so easy to find a replacement manager.  After a fruitless search for a local manager, the league entered the Internet age as GM Jed became the full-time manager, via the Internet.