What is "conquistadores"

Usage examples of "conquistadores".

Indonesia, say, or in the Caribbean on the outskirts of a Mesoamerican civilization untouched by Conquistadores, or in Norse colonies on the shores of the Black Sea?

Or, given many cultures and many alternative historical skeins, isn't it likely that the right combination of factors would come into play somewhere else, sooner or later - in the islands of Indonesia, say, or in the Caribbean on the outskirts of a Mesoamerican civilization untouched by Conquistadores, or in Norse colonies on the shores of the Black Sea?