Garfield County isn't exactly a new idea. The first Garfield County in Kansas was formed in the late 1880s, but was declared illegal by the state a few years later because it didn't meet the state's minimum area requirement for new counties (apparently Wyandotte County was exempt from this requirement). This declaration was probably for the best at the time, since the good citizens of Eminence and Ravanna, in zealous pursuit of the county seat, were quickly exterminating each other. A hundred years later, it appears that neither side won since both communities are now extinct. Kalvesta could join them any day, so any action to form a new county should be taken soon, while there's still someone there to care.
This incarnation of Garfield County is 144 square miles larger than its predecessor to get past that pesky size requirement.