Before Columbus’ discovery, North America (and South America as well for that matter) were inhabited mostly by tribal nations. Columbus came, and with him, the Europeans. They flooded to the New World, mostly for religious reasons, be it protestants trying to escape the tyranny of Catholic monarchs and popes, or people simply looking for a fresh start in the New World where they could begin their own little subset of Christianity. Eventually this would lead to the creation of the United States of America, the most powerful country to this day.
Columbus discovered America in 1492. Before then, only one group of Europeans had set foot in the New World, and that was the Vikings during the time of Erik the Red. Their settlements didn’t last, and it is doubtful if they even knew of the giant continent they had set foot upon. However, this land was still inhabited by the native peoples, the largest group of which are the Hopewell and Anasazi tribes. These native Americans were eventually driven off their own land by the Europeans when they claimed the land.
After Columbus arrived, the floodgates opened wide. Europeans came flooding in from several different nations to take the land for themselves, establish colonies, and eventually, seek great wealth from the treasures they assumed the land held for them. The British colonies were the most famous ones by far. Eventually they gained independence from Britain and became the United States of America, the most powerful nation in the world today.