Adams' most recent opera, "Girls of the Golden West" (2017), with a libretto by Sellars based on historical sources, is set in mining camps during the California Gold Rush of the 1850s. Sellars described the opera this way: "These true stories of the Forty-Niners name for people who took part in the 1849 Gold Rush are overwhelming in their heroism, passion and cruelty, telling tales of racial conflicts, colorful and humorous exploits, political strife and struggles to build anew a life and to decide what it would mean to be American."