Aren't most people in America descended from the British? That is to say, the British. Then I want to ask what is the name of that nation?

British and American people are collectively referred to as Anglo-Saxons in the United States. This title has been used for hundreds of years, but it is rarely used today. Because British-Americans are mixed with other races, they use a broad title of non-Latino white.

It is worth noting that the term Anglo-Saxon does not apply to Scots, Irish and Northern Irish (Presbyterian Irish, also known as Scottish-Irish), but Welsh people are often mixed with British people, so this term applies.

The British and Celts in the United States belong to the Atlantic White Atlantic Baltic type. Although they are close to the northern Europeans and the northern French in appearance, they have their own unique characteristics, so it is usually difficult for us to distinguish the Scots from the British.

Especially in the19th century, the immigrants from the British Isles were called the ethnic groups in Northwest Europe and regarded as the main ethnic groups in the United States.