Clearly Spain is the place that Spansh people originated in. But just over 500 years ago Spain began colonising large parts of the world, as Britain did a couple of hundred years later. Inevitably there was mixed breeding between the Spanish invaders/colonisers and native populations and African slaves brought in. SO the population of much of the Americas is of mixed race.
Note also the colonies of Portugal (Brazil), Britain, France, Netherlands, etc in the Americas, with similar mixed racial history.