Christopher Columbus did more than discover a new world. He changed the Old World. Through his adventures, he launched Europe's most powerful nations into an era of exploration and colonization - and, in the process, touched off a brutal period of genocide and slavery that would continue for centuries. But while we all think we know everything we need to know about Columbus, he remains an enigmatic figure. Only scholars are familiar with some parts of his remarkable life. Here, from historian Anna Abraham, is his full story.