Complex sentence: Beginning in the late 15th century, large numbers of Iberian colonists settled in what became Latin America (Portuguese in Brazil and Spaniards elsewhere in the region), and at present most white Latin Americans are of Spanish or Portuguese origin.
Split into simpler sentences: Beginning in the late 15th century, large numbers of Iberian colonists settled in what became Latin America. At present, most white Latin Americans are of Spanish or Portuguese origin.