The senior Stearns later opened a private preparatory school for boys in Medford; many students came from the American South and the West Indies.

They met through acquaintances, including her father Warren Preston, a probate judge in Norridgewock, Maine; and Lydia Maria Child, an American abolitionist and women's rights activist, who was her aunt.

[1]: 59 Before voting in the Missouri and Kansas territories about the future of slavery in each jurisdiction, Stearns was one of the chief financiers of the Emigrant Aid Company.

He also established in his Medford mansion an important station of the Underground Railroad to help escaped refugee slaves to gain freedom (some continued to Canada, which had abolished slavery).

Massachusetts Governor John Andrew asked Stearns to recruit the first two Northern state-sponsored black infantry regiments.

[2] After President Abraham Lincoln's Emancipation Proclamation in January 1863, Stearns worked tirelessly for the civil rights of African Americans.

Among his many admirers and friends were Louisa May Alcott, Henry David Thoreau, Charles Sumner, Frederick Douglass, and President Andrew Johnson.

Writer John Greenleaf Whittier published a poem in honor of Stearns in the May 1867 edition of the Atlantic Monthly, entitled "G.L.S."

In 1897, a monument was erected on Boston Common to commemorate Colonel Robert Gould Shaw and the 54th Massachusetts regiment he commanded.

The tablet is entitled: "In Memoriam George Luther Stearns" and says, in part:[5] A merchant of Boston who illustrated in his life and character the nobility and generosity of citizenship.

To his unresting devotion and unfailing hope, Massachusetts owes the Fifty-fourth and Fifth-fifth Regiments of colored infantry, and the federal government ten thousand troops, at a critical moment in the great war.