Today’s battles over Christianity in U.S. public schools have deep roots. In the nineteenth century it was an intramural struggle between Protestants and later-arriving Catholics. But at Christmastime in 1905, when Frank Harding, the Presbyterian principal of a Brooklyn elementary school, urged his Jewish students to be more like Jesus, the Jewish community entered the fray in a big way. It was just the trigger Orthodox Jewish activist Albert Lucas had been waiting for. Fresh from battling Christian settlement houses intent on converting Jewish children, Lucas accused the public schools of illegal proselytizing and called for Harding’s ouster. After the Board of Education let Harding off in 1906 with a slap on the wrist and declined to clarify the rules governing religion in schools, New York’s Jews staged a boycott of school Christmas pageants in protest. The board’s concession to exclude sectarian hymns and religious compositions generated enormous antisemitic public backlash. Jews were accused of waging war on Christmas and of being less than true Americans. The Great Christmas Boycott of 1906 traces the Christmas celebration dispute to the present day and describes how Jewish organizations of the twenty-first century, persuaded that politics are unlikely ever to permit a victory, seem to have reconciled themselves to the status quo and moved on to other, more winnable issues.