Why is "Black Belt in the American South" trending?

Wikipedia Overview

The Black Belt in the American South is a geopolitical region comprising areas with both historical and current majority African American populations. The term for the geopolitical region comes from that of the geological formation known as the Black Belt, named for the highly fertile black soil, and the history of the region regarding slavery. Historically, the Black Belt economy was based on cotton plantations – along with some tobacco plantation areas along the Virginia–North Carolina border. The valuable land was largely controlled by rich whites and worked by primarily black slaves, who in many counties constituted a majority of the population. As the term applies to the sociopolitical region, it generally describes a region larger than that defined by its geology.