Short answers, pulled from the story.
The word slavery entered Middle English through Old French and ultimately derives from Byzantine Greek terms meaning prisoner or captive. One historical view suggests this term came from the Slavic tribe name Slověne, who were often captured and enslaved during the 8th or 9th century.
As many as seventeen million people were sold into slavery on the coast of the Indian Ocean, Middle East, and North Africa between 1500 and 1900. This trade included routes across the Arabian Peninsula and Trans-Saharan routes used by slaves traveling to the Sahara desert.
Brazil became the last country in the Western world to abolish slavery in 1888. Nearly five million slaves were brought from Africa to Brazil between 1501 and 1866 making it the largest destination for trans-Atlantic trade.
The United States ratified the Thirteenth Amendment banning involuntary servitude except as punishment for crime in December 1865. This legal change followed earlier abolition efforts such as Britain ending slavery across much of its empire in 1833.
More than fifty percent of modern slaves provide forced labor usually within factories or sweatshops of private sectors. Human trafficking primarily involves women and children forced into prostitution becoming the fastest growing form of unfree labor today.