The promise of racial and religious integration in American private schools faced a critical test at Boston's Commonwealth School between 1958-1972, where Jewish, Protestant and Black students navigated complex social dynamics in an ambitious educational experiment. As headmaster during this period, I documented the evolving relationships between these groups through ethnographic observation and reflective analysis, tracking a student population that was approximately 40% Jewish, 45% Protestant, and 15% Black. While interfaith initiatives including religious education, chapel services, and Bible study successfully bridged Jewish-Gentile divisions in the early years, the increasing enrollment of Black students from 1960 onwards revealed deeper challenges. Initial Black students thrived academically and socially, but subsequent cohorts struggled with academic performance, social isolation, and disciplinary issues, leading to segregated social spaces and confrontational incidents. The 125-student institution's experience highlighted how forced integration, though creating opportunities for political negotiation and cross-cultural learning, failed to resolve fundamental barriers to mutual respect and authentic relationship-building between racial groups. Rather than achieving meaningful integration, the school settled into an uneasy coexistence that reflected broader societal tensions of the era.