O’Brien

Formed December 15, 1851 (74^th county)

O’Brien County (14,187), Primghar (906), Sheldon (5,513)

The masonry and concrete Neo-Classical building in Primghar was built in 1914.  The facility is on Hayes, 1^st, Green, and 2^nd streets.  United States Highway 59 is one block east.  Smith and Keffer are the building architects.  The facility features faux columns.  There previously were 1860, 1874, and 1887 courthouses since the county founding on December 15, 1851.  The county was taken from Cherokee County as the 74^th county.  Old O’Brien was the first county seat until 1873 when Primghar took over.  Irish patriot William Smith O’Brien is the inspiration for the county name.  The county seat name comes from the first initial of eight settlers. 

O’Brien County government consists of a sheriff, a recorder, an attorney, a treasurer, and an assessor (executive).  It has 5 Supervisors (legislative.)  Twenty District Court Judges and Fourteen Magistrates serve O’Brien, Buena Vista, Cherokee, Clay, Crawford, Dickinson, Emmet, Ida, Lyon, Kossuth, Monona, Osceola, Palo Alto, Plymouth, Sioux, and Woodbury counties (judicial.) O’Brien County is located in the northwest part of the state.  Sioux City, Iowa is southwest and Des Moines, Iowa is southeast.  The county center is 2.8 miles Northwest of Primghar.  The county is surrounded clockwise by Osceola, Dickinson, Clay, Buena Vista, Cherokee, Plymouth, Sioux, and Lyon counties. 

The county has an area of 573 square miles.  It is 40 of 99 in the state.  It ranks 56 out of 99 in population in the state.  It has a density of 24.8 persons per square mile making it 54 out of 99 in the state.  O’Brien County has 77.7% of its population in its incorporated areas.  United States Highway 18 crosses east to west through the county from Clay County to Sioux County.  United States Highway 59 travels north to south from Osceola County to Cherokee County.  The county is a square.  Primghar is located near the center of the county.  Sheldon is on the northwest border of the county.  Primghar is the county seat and Sheldon is the largest city.  Primghar is 6.4% of the county population while Sheldon is 38.9% of the county population.  The county seat is pronounced PRIMG-HAR.