More than 180,000 historical markers dot the U.S. in a fractured and confused telling of America — where offensive lies live with impunity, history is distorted and errors are both strange and funny.

The sound of the party filters across the mansion's lawn long before you see it: Dozens of guests spill out onto the front porch of the stately Fendall Hall in Eufaula, Alabama. It's an engagement ...