Adams County was created on January 13, 1825 - formed from Pike County and Unorganized land. The County was named for John Quincy Adams, sixth President of the United States. Marquette County was formed in 1843 from Adams County, and abolished in 1847.
If you have any more information or media of Illinois' former Marquette County, please send it to meprovine@yahoo.com, and I'll post it on the blog.