Sac County was given its permanent boundaries by the act of January 15, 1851. The southeastern portion of the county, about one-third of it, was acquired from the Sac and Fox Indians through the treaty of October 11, 1842. The rest of the territory had been acquired by the United States as early as 1830, in which year the Sacs and Foxes, Omahas, Iowas, Otoes, Missouris and various bands of the Sioux ceded all their claims to Western Iowa. 

From 1837 to 1843, the southern tier of townships of Sac County was included within the limits of the original County of Benton, the remainder being within the borders of the original County of Buchanan. But it was not until 1851 that the county acquired its boundaries and its very appropriate name which has identified it in history with a great Indian tribe which was one of the last of its race to stand against the white man of destiny. 

In January, 1853, the General Assembly passed a law declaring the counties of Adams, Cass, Harrison, Shelby and Wahkaw (now Woodbury) organized after the first Monday in March, 1853. The unorganized counties were attached to them for election, revenue and judicial purposes; eleven of them, including Sac County, were attached to Wahkaw. On January 28, 1855, the county was attached to Greene for these purposes. 

The first settler in Sac County was Otho Williams, who, in 1854, located at Big Grove in the southeastern corner on the North Raccoon River, where he cleared a farm in the woods while thousands of acres of fertile prairie land, ready for the breaking plow, surrounded the grove on all sides. Soon afterward, F. M. Corey, Leonard Austin, Joseph Austin, W. F. Lagourge and Seymour Wagoner settled in various parts of the county. Mr. Wagoner became a major of cavalry during the Civil war and was killed in battle. 

Greene County, to which Sac was attached, had been organized in 1854, and in the following year the increasing residents of Sac County united for independent organization. A majority of them petitioned William Phillips, the county judge of Greene, for that privilege. He granted it, and on the 4^th of July, 1855, a town was laid out on the banks of the North Raccoon and named Sac City, and selected as the county seat. The first house at Sac City was built by Eugene Criss for a hotel, which was for many years the station for the semi-weekly stage line running between Cedar Falls and Sioux City. 

The first election in Sac County was held on April 7, 1856, when thirty-seven votes were cast altogether. Samuel L. Watts was elected county judge; F. Lagourge, sheriff; H. C. Crawford, prosecuting attorney; F. M. Cory, treasurer and recorder; Jacob McAfer, drainage commissioner. 

A second election was held on May 10, 1856, and the first entry in the official records relates to that event. Then, on December 7, 1857, appears the following as an indication of the prevailing salaries of those days: “And now comes the citizens and tax payers of Sac County, Iowa, praying for an increase of salary for the following officers: County judge, clerk of district court and recorder and treasurer. It is asked in the petition be raised from fifty dollars to ninety-nine dollars per annum commencing with August, 1857.” 

Previous to organization, the three commissioners appointed to locate a county seat selected a point about six and a half miles west of the east line of the county, on the west bank of the North Raccoon adjacent to a fine tract of timber. On July 4, 1855, the town site of Sac City was laid out by John F. Duncombe, a Fort Dodge surveyor. The first house built was a large log building by Eugene Criss, who opened it as a hotel. He was obliged to haul the windows, doors, nails and the lumber used for finishing, from Dubuque, 270 miles distant. The second house was erected by James Ganna. 

The nearest postoffice “convenient” to Sac City was at Fort Dodge, fifty miles away, and the messenger delegated to go after the mail was paid 25 cents for every letter which he brought to any settler at the county seat. 

Sac City’s early growth was due to the good water power of the North Raccoon and the fine body of timber at and near the town site. So that by 1875 it was a brisk little village with several mills, a new and substantial courthouse recently completed, and a number of prosperous business houses. It was decidedly the largest, as well as the oldest, town in the county. With the coming of the Chicago & North Western and the Chicago, Milwaukee & St. Paul, its standing was beyond dispute by Odebolt, or any other town in the county; and as to location, Odebolt was farther to the southwest than Sac City was to the northeast. The county seat has now a population of about 2,800. 

In 1877, the Chicago & North Western Railway Company built a new extension from Maple River Junction, near Carroll. Several years before, large colonies of Swedes had settled in Northern Crawford County, with the Kiron region as their nucleus, and when that line was built towns were laid out near the Swedish settlement such as Wall Lake, Odebolt, Arthur and Ida Grove. The most important of these towns emanating from Kiron was Odebolt. It has grown to be far larger and more influential than the parent colony. The industrious and far-seeing Swedish farmers soon organized to sell grain and live stock, a large elevator was erected, lumber and coal yards were established, a new mail route was opened running between Denison and Odebolt, and the new town was soon making a solid advance in every direction. It now has a population of about 1,500 people and is an incorporated town. It is supported by a fine grain and live stock country and is also a busy shipping point for flour, butter, eggs and general produce. It has also the distinction of being the center of one of the most productive popcorn districts in the country. As it has three good banks, it is also the financial center of quite an extensive area. 

Lake View and Wall Lake are popular summer resorts—the one north and the other south of the picturesque body of water by the latter name. Their normal population is about 800, but during the summer months those figures are much increased. These towns by no means depend exclusively upon such temporary support for their substance and growth, as they are surrounded by a rich country and are constant shippers of live stock, grain, produce, poultry, butter and eggs.