They didn’t really in the earliest times. There was not one people who were Native Americans. There were hundreds of nations. They did not work together. When English people landed to make a settlement in Massachusetts in 1621 there had been thousands of cod fishermen from at least five nations landing up and down the coast for 100 years. Neither side had the slightest ideas how disease worked and had no way to prevent it or cure it if they had known. Thus epidemics were transmitted through trade. Some even swept through trade routes all the way from Mexico and Florida (in 1565) where the Spanish were enslaving and also transmitting disease to people. These virgin ground epidemics killed 30–90% of populations. And they happened about every ten years on average and killed the same percentages. The political and social, cultural, religious and other upheaval of losing more than half of your population in a few years or even in 6 months is enormous. In many places were Europeans landed the villages were abandoned. The farm fields were going back to forest and many thought the meadows were natural, though they were not.
The first really major war that American settlers had was not until 1675–78 in “King Phillips War” (Metacomet). By that time there were 80,000 Europeans in New England in 110 towns. There were 16,000 men in militias. The Native Americans in the area had reduced to about 10,000 people. They were not the same culture and although they spoke related languages they had often been at war with each other. They had all taken up European weapons and had plenty but they had far fewer fighting men (about 2500) and they did not train in militias. They did not have unified leadership. They did not have traditions of obedience in battle. One could not order them to fight in tactical ways as much. The did not have the same sort of garrisons and stockades and forts. The Europeans had Native American allies as well which helped them even more. The Native people attacked and burned and forced Europeans out of about 40 towns in the north. There were many refugees in the Boston areas. The Mohawk attacked their traditional enemies when they were busy attacking the Europeans. It was impossible to grow crops when at war with the Europeans. The French were helping in the North against the English, but it was not enough. In the end they lost. It is amazing they lasted as long as they did. More than 1,000 colonists and 3,000 Native Americans had died, most by disease. Man Native people were enslaved and many sold to the Caribbean. But the European settlement had low death rates, lots of food and doubled about every 25 years. Man of the defeated Native pole fled north where the war continued for several decades in one way or another.
In some places like in what is now Quebec City in 1541, the French were repelled by First Nations attacks and bad weather. But the Europeans would then just try in another place. Information was shared about where was good or bad to settle. But the Native people were just as likely to be in conflict with a neighbor a short distance away as they were to be in an alliance. There were hundreds of languages and cultures in North America. The Europeans were just a handful. In other places they came and held by force. But most places they found recently emptied places or made deals with native people. Native Americas in some places were interested in siding with the new people in alliance against native enemies. Other places were interested in trade.
The problem in the end was that there were about 100 million people in Europe in 1500. The high estimate (and most think it is too high, it was probably half that) was that there were 18 million Native people living in what is North America in 1500. Many Europeans had lived for generations in dense dirty cities with no sanitation. Others had lived for generations with domestic animals, often in the same living space, for generations. They had many diseases and some immunity. And there were huge numbers of them. Everyone in Europe followed versions of the same religion for the most part. They spoke languages in one language family. They all had similar concepts about politics and leadership. They were grouped in a handful of large powers. They all had armies and navies. The Native people that did form more Nation state sort of structures or alliances did hold off Europeans much longer. The Six Nations and the Cherokee, Pontiac, Red Sticks, the Iron Confederacy and many others. The Six Nations were an important part of Great Nation diplomacy and wars for generations. The Cherokee were viewed by the English as a separate nation for 150 years. The Pueblo people united their different cultures for a revolt that defeated the Spanish and killed and drove them off from 1680–92. But in the end everywhere there were always more Europeans coming. The epidemics kept happening and it was hard to united across multiple cultures to fight off the Europeans.
Buddhist teachings were translated into Chinese. Then, with the breakdown of the Han dynasty, conversions to Buddhism spread among China's masses. They learned respect for India and they felt compelled to re-examine the theory that the Chinese emperor was the Son of Heaven and enthroned at the center of the world. I hope this helps.
