She landed the Marines at Vera Cruz, Mexico, to assist in the occupation of that city resulting from the arrest of the crew of a whaleboat of "Dolphin" (PG-24) by soldiers of General Huerta, aspirant to the Mexican presidency. During the tense months that followed, "Hancock" transported refugees uprooted by the Mexican Revolution between the coast of Mexico and Galveston, Texas, as she delivered supplies for the United States Expeditionary Force in Mexico.