Native Americans did arrive here via the Bering Land Bridge, so their heritage is a combination of Eastern European and Siberian tribes.
As many of the Native Americans have since intermarried with Europeans or African Americans, this group might also be interested in finding out more about their background in either of those directions.
The National Archives are a wonderful place to start your research, regardless of where you or any of your antecedents came from.
Their website will provide links to enable nearly anyone to research their family genealogy.
Whether your family hailed from China, Russia, England, or Ethiopia, links can be found to provide you with at least a good start for your research.
Many of the important genealogical facts are available right at the National Archives or at the Library of Congress.
While earlier records may be sketchy, especially in the case of African Americans brought over as slaves, or in the case of indentured servants from England or Ireland, the individuals who survived, and their immediate descendants can often be found in some sort of documentation, even if it is something as banal as a bill of sale.
Papers of emancipation can also provide clues as to an ancestor as well.
There were several great waves of migration into the United States during the 19th century, most notably from Europe and China.
Passenger lists recorded at the port of entry can often provide information about the first ancestor to arrive here.
Some of these Genealogy records will also list the town or village where the person originated, as well as their profession in the old country.
The port of embarkation is also listed, so if resources are available, research might also be carried out from that geographic point.
If you are lucky, you might even be able to locate relatives in the old country.