principal streams traversing the county and their banks are covered with timber.
The county was entirely unsettled in 1846 when the Mormon emigration began from Nauvoo westward through Iowa. At this time many of the Musquaka Indians, under their chief, “Johnny Green,” occupied hunting grounds along Grand River. A large body of Mormon refugees moving westward were overtaken by severe winter storms in Decatur and Union counties. Several hundred men, women and children, unable to endure the hardships of winter travel through an unsettled country, stopped in a grove on the Grand River bluff in Union County and dug caves for shelter form the storms. Here they also built log cabins and cared for the sick and feeble until spring. They built a mill run by horse power and many remained several years cultivating land and raising crops. This furnished a refuge for others who could here recruit from the hardships of the journey and replenish their exhausted provisions. The place was named Mount Pisgah by the Mormons.
In 1850 many settlers came into the county and purchased the improvements made by the Mormons. Among them were William L. Lock, J. H. Stark, Joseph and Norman Nun and Benjamin Lamb. Henry Peters bought the Mormon mill and laid out a town which he named Petersville. A store, hotel and several small houses were built and for a few years it was the business center for the people of the county. In 1851 Amos C. Cooper and Isaac P. Lamb settled in the southern part of the county in Pleasant township and the following year William Grosbeck and Lewis Bragg located in the northeast corner.
The county was organized in 1853 by the election of Norman Nun, judge; John Edgecomb, sheriff, and I. P. Lamb, school fund commissioner. The first term of court was held at Petersville in the fall of 1853 at which Judge A. A. Bradford presided. The commissioners located the county-seat near a beautiful grove on Twelve Mile
