Final answer:
The first census after Tennessee joined the Union took place in 1800.
Step-by-step explanation:
The date of the first census after Tennessee joined the Union was in 1800. Tennessee became the 16th state of the United States on June 1, 1796, and the first census conducted after its admission took place four years later. The purpose of the census was to count the population and gather demographic information for each state.
Learn more about Tennessee's first census after joining the Union