olathe was incorporated in 1857. it was not the first city in johnson county. because it grew very quickly, it became the county seat in october 1859. growing hatred across the united states about the issue of slavery led to many fights between abolitionist settlers and nearby slave state missouri. these fights would grow, and they would become a part of the bigger fight known as bleeding kansas. when kansas became a state in 1861, it was a free state. when it became a state, violence stopped. peace, however, would continue to elude olathe for many years to come. in 1861 union officials and local military forces created a military post in the city. it had one company of soldiers, and it had the local militia.