Racism in history

I was reading today of Benedetto Dei. Dei was a Florentine merchant, an agent of the merchant house of Portinari, in the mid 15th century. Benedetto Dei travelled in Africa and was the first white man to visit Timbuktu. Of course Africans had lived there for centuries,Berbers and Arabs( aren't they white?) had been running trans Saharan caravans for years. So what's the significance that accords Dei his spot in history? The first white man(read European). We know Chris Columbus "discovered" America while he was lost in the Atlantic thinking he was off the coast of India. Sir Edmund Hillary conquered Everest, though doubtlessly Tibetan monks, who have a love of high places, had been there before. The examples are endless. The 16th-19th centuries are often called "The Age of Discovery". It's as if these places didn't exist until a European white man showed up to "discover" it. And of course, this arrogance led these Europeans to now claim, that since they "discovered" it, they owned it and began that sad and terrible experiment called colonialism, the end results of which still plague us today. It just doesn't count unless you're white.