<P> Conflict over resources on North America ensued in various wars between these powers, but, gradually, the new European colonies developed desires for independence . Revolutions, such as the American Revolution and Mexican War of Independence, created new, independent states that came to dominate North America . The Canadian Confederation formed in 1867, creating the modern political landscape of North America . </P> <P> From the 19th to 21st centuries, North American states have developed increasingly deeper connections with each other . Although some conflicts have occurred, the continent has for the most part enjoyed peace and general cooperation between its states, as well as open commerce and trade between them . Modern developments include the opening of free trade agreements, extensive immigration from Mexico and Latin America, and drug trafficking concerns in these regions . </P> <P> The specifics of Paleo - Indians' migration to and throughout the Americas, including the exact dates and routes traveled, are subject to ongoing research and discussion . For years, the traditional theory has been that these early migrants moved into the Beringia land bridge between eastern Siberia and present - day Alaska around 40,000--17,000 years ago, when sea levels were significantly lowered due to the Quaternary glaciation . These people are believed to have followed herds of now - extinct pleistocene megafauna along ice - free corridors that stretched between the Laurentide and Cordilleran ice sheets . Another route proposed is that, either on foot or using primitive boats, they migrated down the Pacific coast to South America . Evidence of the latter would since have been covered by a sea level rise of hundreds of meters following the last ice age . </P> <P> Archaeologists contend that Paleo - Indian migration out of Beringia (eastern Alaska), ranges from 40,000 to around 16,500 years ago . This time range is a hot source of debate and promises to continue as such for years to come . The few agreements achieved to date are the origin from Central Asia, with widespread habitation of the Americas during the end of the last glacial period, or more specifically what is known as the late glacial maximum, around 16,000--13,000 years before present . However, older alternative theories exist, including migration from Europe . </P>

Where did the first societies in north america come from