named for the Platte River. Platte County, Wyoming: Platte is named for the North Platte River. Platte is French for flat. Plumas County, California: Plumas is named for Spanish name for the Feather River (Rio de las Plumas), which flows through the county. Powder River County, Montana: Powder River is named for the Powder River, which in turn was named for gunpowder-like sand along its banks. R Racine County, Wisconsin: Racine is named for the Root River, racine being the French word for root. Rappahannock County, Virginia: Rappahannock is named for the Rappahannock River, named in turn for the Rappahannock Native American people. Red Lake County, Minnesota: Red Lake County is named after the Red Lake River, named by the Ojibwa for its reddish sand and water. Red River County, Texas: Red River is named for the Red River. Red River Parish, Louisiana: named for the Red River Redwood County, Minnesota: Redwood County is named after the Redwood River, which flows through the county. Republic County, Kansas: Republic is named for the Republican River, which in turn was named for the Pawnee Republic which once existed near the river. Rio Arriba County, New Mexico: Rio Arriba is named for its location on the upper Rio Grande. (Rio Arriba is "upper river" in Spanish.) Rio Blanco County, Colorado: Rio Blanco is named for Rio Blanco, or, in English, the White River. Rio Grande County, Colorado: Rio Grande is named for the Rio Grande, which runs through the county. Rock County, Wisconsin: Rock is named for the Rock River. Roseau County, Minnesota: Roseau County is named after the Roseau Lake and Roseau River. Rosebud County, Montana: Rosebud is named for the Rosebud River, which was named for the many wild roses along the banks of the river. S Sacramento County, California: Named for the Sacramento River Saline County, Arkansas: Named for the Saline River. Saline County, Illinois: Named for the Saline River. Saline County, Kansas: Named for the Saline River. San Benito County, California: Named for San Benito Creek. San Juan County, Colorado: Named for the San Juan River and San Juan Mountains. San Juan County, New Mexico: Named for the San Juan River. San Miguel County, Colorado: Named for the San Miguel River. Santa Cruz County, Arizona: Named for the Santa Cruz River. Sangamon County, Illinois Named for the Sangamon River. Scioto County, Ohio: Named for the Scioto River. Sevier County,