Final answer:
The beginning of Spanish colonization in present-day United States started in the American Southwest, including parts of California, Arizona, New Mexico, and Texas. The Spanish influence remains through landscapes and land grants, and their control extended from the Caribbean and Mesoamerica into North America following Columbus's discovery.
Step-by-step explanation:
The area of present day United States that marked the beginning of vast colonization by the Spanish is the region now known as the American Southwest, which includes states like California, Arizona, New Mexico, and Texas. During the 1500s, following Christopher Columbus's discovery, the Spanish empire expanded its reach from the Caribbean and Mesoamerica to the vast territories of North America. The Spanish influence is still evident in American culture, particularly through Spanish landscapes, forms of settlement, and Spanish land grants that shaped the region's development.
Spain's colonization efforts in North America also left a lasting impact through the introduction of European diseases like smallpox, which caused a significant decline in the indigenous populations. Despite the dominance of England and France along the eastern coast of North America, the Spanish moved from Mexico into the southwest, controlling these areas for many years and incorporating them into the broader Spanish Americas. This period of history significantly influenced the social, political, and cultural landscape of what later became the United States.