I will start with the year the Civil War ended, 1865.
This fashion plate appeared in Godey’s Lady’s Book. Of course, don’t imagine the dresses beautifully drawn here were worn by the large majority of American women. Most families were still affected by the war. I suppose there were some, perhaps Yankee women, who afforded to follow the (usually Parisian) trends. So look at fashion plates as you look at today’s Vogue.