[3] Archaeology at Platt Island in the Big Cypress National Preserve shows humans settled in what is now Collier County more than 2000 years ago.

It was named for Barron Collier, a New York City advertising mogul and real estate developer who had moved to Southwest Florida and established himself as a prominent landowner.

Virtually the entire southeastern portion of the county lies within the Big Cypress National Preserve.

The northernmost portion of Everglades National Park extends into the southern coastal part of the county.

As of the 2010 census, 83.85% of the population was non-Hispanic Whites, 25.9% was Latino or Hispanic, 6.6% was African American, and 1.1% was Asian.

[16] As of the 2020 United States census, 375,752 people, 140,578 households, and 97,279 families resided in the county.

All locations offer public internet stations, printing, photocopying, free Wi-Fi, and 24/7 drop boxes for book and video returns.

[19] According to the Secretary of State's office, Republicans comprise a majority of registered voters in Collier County.

All voter information is as of September 30, 2022[update], and provided by Collier County Supervisor of Elections Office.

A three-month effort at the beginning of 2016 netted over one ton of captured snakes, including a Florida record for the largest male Burmese python, measuring 16 ft and weighing 140 lb.