What was the US Population in 1776?

Nobody knows.

But, the first census was done in 1790. The population of the U.S. was found to be 3,929,214 people. In 1776, at the time of the Declaration of Independence, historians estimate the population to have been about 2.5 million people. That is less than the population of San Diego County today.

The 1790 census included approximately 700,000 slaves.

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