@Rogar, friend, I am afraid I will need to kindly reinforce the idea that Spanish isn't Portuguese, different languages (since the dawn of days), slightly different culture, our history is basically of conflict and competition since always... Etc...
That isn't to say that the Spanish did it. We all helped making modern racism, and the Iberian countries were the first europeans to start the african slave trade. Still, racism isn't a portuguese nor even spanish construction, it is much older and also with developments long after the portuguese were out of the picture.
But yeah, since exploration was the kick-start of the putting in practice on what ended up becoming massive levels of slavery, we were instrumental in that, given that we basically "discovered" almost the whole world (Africa, Brazil, the route to India, and if we are being literal, we probably also discovered the Americas, given that there is 59.9% chances of Colombo being Portuguese, 40% of being Spanish and 0.1% of being Italian).
@idonotlikeusernames, As you said, we all have our share of fault on the issue. We were ones of the first to dable with slave trade, we gained a lot of money with it, despite being the first ones to abolish in European ground, we took a long time abolishing it in the colonies, and we kept trading even after it was prohibited. So yeah, Portugal had an important role in creating the modern reality of racism. Still, we can't say the dutch, spanish, or portuguese were the ones responsible. We all were, and none of us trully created it, it was a reality that already existed in Europe and beyond (I had no idea about the Ottomans), and it kept developing and changing after portuguese and dutch started to become secondary and even irrelevant.