Rhiannon Giddens has always been keenly aware of the arc of American history -- the Carolina Chocolate Drops, the 2000s band she once led, was designed as a critique of the darker moments of Americana -- but Freedom Highway, her second solo album, puts her intent into perspective.

Where her 2015 solo debut, Tomorrow Is My Turn, was essentially a covers album, gaining its importance through context, Freedom Highway relies on originals, but the past is never far behind.

This should be expected from Giddens, who is at her core a folk artist building upon -- and expanding -- tradition, but it's still startling to realize how she establishes a vernacular at the outset of Freedom Highway, then explores all of the possibilities of African-American folk music on the album.

"At the Purchaser's Option," the song that inaugurates Freedom Highway, explicitly evokes slavery, and it's spare and haunting, standing in contrast to the title-track closer, a funky number that illustrates how far African-Americans have traveled during the course of the history of the United States.

Throughout Freedom Highway, Giddens plays with this idea -- how oppression gave way to freedom -- and it's not just through her lyrics, but how the music expands as the album reaches its conclusion: at the outset, it seems austere, but by its conclusion it's a robust celebration of all the weird, wonderful parts of America.

This isn't an accident.

Freedom Highway draws upon deep American traditions, and while its form may be a throwback, it speaks to a time when the phrase "Black Lives Matter" can be seen as controversial and, in doing so, it illustrates how these issues are deeply ingrained in American life and cannot be forgotten.