It all began in the 1860s when several liberal Unitarian Christian families moved from Boston to the suburb of Grantville, as Wellesley Hills was called then, when the railroad arrived. With no Unitarian church in town, they found a minister they liked in Needham, managed to lure him away, and rented Maugus Hall, a town community center, for services.

Out of humble beginnings in 1871 grew a congregation that not only became prominent in Wellesley and the denomination but also made a significant, lasting impact on the world. Wellesley Unitarian ministers:

• saved hundreds...