There are eight Cherokee counties in the United States. Seven of them have historical connections with the Cherokee people. As found in hundreds or thousands of business names, personal names, automobile models, and much more, the name “Cherokee” is greatly overused, more or less indiscriminately. If it were possible for them to collect royalties on such usage, the three recognized Cherokee tribes would together be one of the wealthiest entities on the planet. The Cherokee are probably the best-known worldwide of all American Indian tribes. I am going to refrain–wisely, I think–from commenting on the enormous number of Americans who insist that they have Cherokee ancestors. And, I will have nothing to say here about the 212 groups, at last count, who declare that they are unrecognized Cherokee tribes and remnants. In modern Cherokee, the word is Tsalagi. In the now extinct Lower Cherokee dialect, it was Tsaragi, and it was from this dialect that the name was anglicized to “Cherokee.” Although Tsalagi is not a Cherokee word, it is now the self-designation of the members of the tribes. Its origin is uncertain, but I am inclined to agree with those who believe it may have come from Choctaw, probably from a term meaning either “people who live in the mountains” or “people who live in cave country.” Here are those eight counties, alphabetically by state name, with a brief explanation of how each one acquired its name. Cherokee County, Alabama, was formed from Cherokee lands soon after the Treaty of New Echota was signed, more than two years before the Trail of Tears. Cherokee County, Georgia. Originally, most of northwest Georgia, which then belonged to the Cherokee, was simply designated late in 1831 as that state’s Cherokee County. Within a year, it was carved into nine new counties, and, toward the end of 1832, the Cherokee lands were distributed by lottery to white people. Some of the Cherokee were already being forcibly removed by Georgia in 1831, years before the falsely promulgated Treaty of New Echota. The remnant after the other nine counties were created—and a part of it used to form Milton County in 1857—is the present Cherokee County. To be historically blunt, the State of Georgia was the most brutal of all states toward the Cherokee. Here are maps of the Cherokee lands in Georgia in 1822 and in 1834. 
Cherokee County, Iowa, lies in the northwestern part of the state. It was one of many formed from “Indian Treaty Lands” in 1851. The name seems to have been chosen because the Cherokee had no connection at all with the area. More details about the historic and prehistoric Indians of Iowa can be found in the Wikipedia article Indians of Iowa.
Cherokee County, Kansas, is the extreme southeastern county of Kansas, bordering Craig County, Oklahoma. Craig County was formed from a part of the Cherokee Nation when the Indian Territory became a state in 1907. Some Cherokee people lived in that part of Kansas beginning in the 1830’s.
Cherokee County, North Carolina, is the westernmost county of the state. It is near the heart of Tsalaguwetiyi [ᎠᎳᎫᏪᏘᏱ], the old Cherokee lands. There are tracts of the Eastern Cherokee trust lands [the Qualla Boundary and non-contiguous parcels] in the county, and it has a significant modern Cherokee population. I would rate it as the most deserving of all the counties bearing the name. [The main part of the Eastern Cherokee trust lands is located in Swain and Jackson counties, with outlying parcels in Cherokee, Graham, and Haywood counties. The Qualla Boundary is sometimes called a “reservation,” but that is not a correct designation.]
Cherokee County, Oklahoma, is at the heart of the Western Cherokee country, formed from a part of the Cherokee Indian Nation, Indian Territory, shortly before Oklahoma became a state. The county seat, Tahlequah, is the capital of the Western Cherokee Nation today. A little more than one-third of the population of the county are American Indians.
Cherokee County, South Carolina. There were some Cherokee [and Catawba and other Indians] using the lands in this area when the white people moved in and pushed them away beginning in the middle of the 18th Century.
Cherokee County, Texas, adjoins the northeastern line of Houston County. It has a complex and sad history of Cherokee settlers and their unfulfilled hopes. You can find more details of that history here.
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