>What year was Mercer Co. formed? > >Cathy > Mercer was formed in 1800. However, the county government was not up and running until 1804. From 1800 - 1804, all Mercer county governmental activities were handled by Crawford County. If you're looking for original tax, probate, etc records for Mercer 1800 - 1804, you must go to the Meadville Courthouse in Crawford County. John MacDonald 1021 Hancock Road Williamstown MA 01267-3021 413-458-0056 macillus@bcn.net