As Ros has shown, there is already a project for Mississippi. If you would like to join the project, follow the instructions on the project page.
Before attempting to start any new project, it is always a good idea to check the current projects. https://www.wikitree.com/wiki/Help:Projects
Be sure to check out the individual projects for sub-projects. Mississippi Project, for example, is a sub-project of the United States History Project.
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