Assuming the information presented in this link is actually accurate...Basically, Columbus wasn't the hero or revolutionary he's been portrayed to be.
He was actually responsible for the slavery of many Native Americans, including the sexual slavery of minors.
Everybody with any bit of education believed that the world was round, including the Queen of England.
The reason he kept returning to America was for gold.
So, basically, he was a terrible person.
Also some information about another figure who should be important in history but isn't.
Or, basically, summed up: Columbus's legacy is a whitewashed invention made by white men.