Where in the world does slavery still occur at the largest scale?

Liberia was created in 1847 by freed slaves from the United States. They es­tab­lished a gov­ern­ment modeled on that of the United States and named its capital city Monrovia after James Monroe, a prom­i­nent sup­port­er of the col­o­niza­tion.

Sahara. The Richat Struc­ture in Mau­ri­ta­ni­a, also known as the Eye of the Sahara, was in­ter­pret­ed as an asteroid impact struc­ture, but no evidence for shock meta­mor­phism has been found. Today sci­en­tists believe that it is a huge (40 km in di­am­e­ter) and deeply eroded geologic dome.

Senegal. The country of Senegal is named after the Senegal River that borders it to the east and north.

Denmark. In 1943, 95% of Jews from Naz­i-oc­cu­pied Denmark were evac­u­at­ed to Sweden in an event known as the rescue of the Danish Jews. It was a col­lec­tive achieve­ment of the Danish re­sis­tance move­men­t, German diplomat Georg Fer­di­nand Duckwitz (who warned the Danish Jews about the intended de­por­ta­tion to Germany) and many ordinary Danish cit­i­zen­s, mostly po­lice­men and fish­er­men.