On July 21, 1970, Chicago performed live at Tanglewood during a pivotal moment in their career, shortly after the release of their second album, "Chicago II," which debuted earlier that year. This album featured hits such as "Make Me Smile" and "25 or 6 to 4," showcasing the band’s unique blend of rock and jazz influences. The live performance, which included the classic "Does Anybody Really Know What Time It Is?", captured the band's dynamic energy and intricate musicianship, illustrating their abilities as both studio artists and live performers. During this period, Chicago was rapidly gaining popularity and establishing themselves as a prominent act in the rock genre, paving the way for future success. Notably, this concert highlights the group's early commitment to live performances, which would become a hallmark of their career, further engaging their growing fanbase.