  shelby county is a county located in the u.s. state of ohio. according to the 2010 census, it had a population of 49,423, which is an increase of 3.2% from 47,910 in 2000. its county seat is sidney. its name honors isaac shelby, former governor of kentucky.  shelby county comprises the sidney, oh micropolitan statistical area, which is also included in the dayton-springfield-sidney, oh combined statistical area. ==history== the algonquian-speaking shawnee native americans had come into the area in the 18th century, displacing the ojibwa-speaking ottawa of the anishinaabeg, a related language group who moved northwest. the shawnee were joined by the iroquois, seneca and mingo peoples as well, displaced by colonial encroachment to the east. in 1792 the european-american pioneer john hardin was killed by the shawnee in shelby county. early settlers named the first county seat of hardin after him. shelby county was created in 1819 from miami county. for many years it contained minster, new bremen, etc.; these were included in auglaize county when it was created from shelby and allen counties. in 1846, a group of 383 free blacks from virginia, called the "randolph slaves", settled in the county, most at rumley. they had been freed by the 1833 will of the virginia [[planter (plantation owner
1819_establishments_in_the_United_States Ohio_counties Populated_places_established_in_1819 Shelby_County,_Ohio