Lyon County, created as Breckenridge county (q. v.) by the first territorial legislature, was not organized until 1858, and did not assume its present boundaries until 1864. These boundaries are as follows: Wabaunsee county on the north; Osage and Coffey on the east; Greenwood on the south, and Chase and Morris on the west. In 1862, the former vice-president Breckenridge having become a secessionist, the patriotic anti-slavery legislature changed the name of the county to Lyon, in honor of Nathaniel Lyon, the Union general who had lost his life at Wilson's creek the previous August.

The first settler was Charles H. Withington, who located in the extreme northern part of the county on the Santa Fe trail, a short distance south of the present town of Allen, in 1846. He opened a store in 1854, which was the first one in the county, and also the only one in southern Kansas outside of the regular Indian posts. His store was a hotel as well as a supply station. Mr. Withington was influential in the settlement of the county and prominent in all public affairs. In April, 1855, Oliver Phillips located on One Hundred and Forty-second creek. He was elected to the legislature in 1859; was a delegate to the Osawatomie convention, and repeatedly held county offices. Chris Ward and J. S. Pigman came about the same time. Others who came during the same year were: Charles Johnson, James Pheanis, David Vangundy, John Rosenquist, Joseph Moon, Rev. Thomas J. Addis (at that time the only free-state man), Lorenzo Dow, R. H. Abraham, William Grimsley, Thomas Shockley, Joseph Hadley, William H. Eikenbery, Joel Halworth, Dr. Gregg, Mr. Carver, James Hendricks, Albert Watkins, John Fowler, G. D. Humphreys and L. H. Johnson. These, with very few exceptions, settled along the creeks in the northem half of the county.

A number of new settlers came in 1856, and a much larger number in 1857. The problem of securing mail now became a serious one. Previous to this time the mail for the settlements had been thrown off the Santa Fe coaches at Mr. Withington's place and was distributed by a horseman at private expense. When the government began giving them their mail by way of Jefferson City and Council Grove and established a postoffice at Columbia, there was a great deal of dissatisfaction, as the settlers did not wish to trust the pro-slavery men who handled it. Finally they secured a box at Lawrence, where all mail was sent, and thence brought by private conveyance to the hotel at Emporia. John Fowler, the postmaster at Columbia in the fall of 1857, resigned and the office was moved to Emporia, where W. H. Fick became postmaster. In August hack lines were established to Topeka and to Lawrence. A great deal of the mail was lost, there being about three bushels of mail belonging to Emporia lying at Osawatomie in Jan., 1858. The next year regular mail routes were established from Council Grove to Fort Scott by way of Emporia, and from Lawrence to Emporia. In Aug., 1860, there were tri-weekly coaches from Lawrence. By March, 1861, Emporia was receiving ten mails per week from different points.

The first school was established in 1858 and taught by Rev. G. W. Torrence. The first newspaper was the Emporia News, founded in 1857 by Hon. P. B. Plumb under the name of the Kansas News. (See Newspapers.) The first sawmill was built by G. D. Humphreys on the Cottonwood river in 1857. The first marriage was between Charles Carver and Sarah Vangundy in Jan., 1856. The first birth was in 1856 in a family by the name of Hennick. The first assessment of property was made in 1858, but was of little value, as the assessor is said to have been prejudiced.

Nearly all authorities give 1858 as the date of organization of the county, although an election for county officers was held on Oct. 6, 1857, which resulted in the election of the Americus ticket as follows: Probate judge, A. I. Baker; sheriff, E. Goddard; treasurer, N. S. Storrs; clerk and recorder, C. V. Eskridge; surveyor, Mr. Voke; coroner, W. B. Swisher; commissioners, H. W. Fick and William Grimsley. Prior to Oct., 1858, the county seat was at Agnes City, which was the residence of Arthur I. Baker, whom the legislature had appointed probate judge. The first term of district court was held on Dec. 20 at Amencus, Judge Elmore presiding. At the general election of 1860 Emporia was chosen as the permanent county seat. Other early towns which figured in the contest were: Fremont, 8 miles north of Emporia, founded in 1857; Waterloo, on the State road 15 miles north of Emporia, laid off in 1858; and Forest Hill, east of the Neosho river opposite the junction, founded in 1858.

In 1860 there were 3,500 inhabitants in Lyon county, but the drouth of that year so discouraged the settlers that many returned east and those who stayed saw actual want and suffering in spite of the relief obtained from Atchison. The next year the breaking out of the war put an end to the already paralyzed activity in business and industry.

The first military company to leave for the seat of war was the "Emporia Guards" in May, 1861. They numbered 50 men and had been drilled by W. F. Cloud, a veteran of the Mexican war. The company took part in the engagement at Wilson's creek, Mo., in August. A. J. Mitchell raised a company of artillery numbering 47 men. L. T. Heritage recruited a company for duty within the state, which became Company B of the Eighth regiment. In the fall of 1862, in response to President Lincoln's call for more troops, 150 Lyon county men immediately offered their services. They were recruited by P. B. Plumb and formed a company in the Eleventh regiment. Soon afterward they were engaged in a battle at Prairie Grove, where several were killed. In 1864, when Gen. Price threatened Kansas, 300 more answered the call to repel the invasion. They were in active duty about a month. Besides this the men of Lyon county played their part in protecting their homes and in driving out hostile Indians in the west and southwest and the bushwhackers in the south.

A number of tragedies occurred in connection with the guerrilla activities between pro-slavery and anti-slavery bands. One of these was the death of Mrs. Carver, who was killed by a free-state mob from Topeka. She was in bed, and the men, on being refused admission to the house, fired into the building at random, two of the shots taking effect in her body. In 1862 occurred the most noted raid in the history of the county. Judge A. I. Baker had called the notorious "Bill" Anderson, his father and brother Jim, horse thieves, and later was obliged to shoot the elder Anderson in self-defense. About the same time a Mexican who belonged to the Anderson gang was hanged by a mob at Americus. A few weeks later the Andersons, with four others, one of whom represented himself to be Quantrill, came to the Baker home, persuaded him to go to his store to get them some whiskey, and just as he was going down the cellar steps shot him a number of times. He drew his revolver and inflicted a flesh wound upon Jim Anderson. The ruffians shot Baker's brother-in-law, Segur, and threw him into the cellar. Then they piled boxes on the cellar door and set them on fire. Baker died before the fire reached him, and Segur escaped by a back window but died a few hours later. All of Baker's property was destroyed by fire and his horses stolen. After a number of other robberies the guerrillas came to the residence of C. H. Withington at Allen. Here they placed all the men under arrest, took what they wanted and destroyed some property. Mr. Withington escaped death through the intercession of Quantrill. At Elm creek they attacked the house of a Mr. Jacoby, whose life was saved by a Santa Fe train which happened to be passing.

The first efforts to secure a railroad were in 1864, but it was not until 1870 that the first road was built. This was the Atchison, Topeka & Santa Fe, which runs south from Topeka. The county issued $200,000 in bonds to aid in its construction. A like amount was voted to the Missouri, Kansas & Texas, which crosses the county in a southeasterly direction and which was built in the same year. Another line of the Atchison, Topeka & Santa Fe from Kansas City enters the county in the east and crosses into Chase county. A third line runs from Emporia south into Greenwood county. The Missouri Pacific crosses the northern part from east to west.

The general surface of the county is prairie, with but few bluffs. The principal streams are the Neosho river, which runs across the county in a southeasterly direction; the Cottonwood river which crosses from west to east and joins the Neosho just above Neosho Rapids; and numerous creeks, of which Duck, Dows and Eagle are the most important. The timber belts along these streams average one-half mile in width, and contain the following varieties: oak, walnut, cottonwood, hickory, elm, hackberry, coffee-bean and locust. Magnesian limestone and sandstone are abundant, and a good quality of potter's clay is found between the Neosho and Cottonwood rivers. The bottom lands along the rivers and creeks comprise about 15 per cent. of the total area.

Lyon is one of the two leading counties in the production of Kafir corn. In 1910 this crop amounted to nearly $300,000. Corn the same year brought $1,750,000; oats, $130,000; wheat, $40,000; tame grass, $170,000; and wild grass, $260,000. Live stock netted $1,630,000; poultry and eggs, $180,000. The total output of the farms for the county that year was nearly $4,500,000. About 400,000 acres are under cultivation. There are 300,000 fruit trees, two-thirds of which are apples. Lyon is the foremost county in the state in the production of live stock. The population, according to the census of 1910, was 24,927. The assessed valuation of property in the same year was $38,600,000.