Springfield is the third and current capital of the US state of Illinois and the county seat of Sangamon County with a population of 116,250 (U.S. Bureau of the Census, 2010), making it the sixth most populated city in the state and the second most populated Illinois city outside of the Chicago Metropolitan Area. Just over 208,000 residents live in the Springfield Metropolitan Statistical Area, which includes Sangamon County and adjacent Menard County. Present day Springfield was first settled in the late 1810s, around the time Illinois became a state. The most famous past resident is Abraham Lincoln, who lived in Springfield itself from 1837 until he went to the White House in 1861. Major tourist attractions include a multitude of historic sites connected with Lincoln. In 1908 a large race riot erupted in the city which culminated in the lynching of two African American residents and led to the founding of the NAACP.

The city lies on a mostly flat plain which encompasses much of the surrounding countryside. There is more hilly terrain near the Sangamon River. Lake Springfield, a large artificial lake owned by City Water, Light & Power company called CWLP, supplies the city with recreation and drinking water. Weather is fairly typical for middle latitude locations, with hot summers and cold winters. Spring and summer weather is like that of most midwestern cities; severe thunderstorms are common. Tornadoes hit Springfield in 1957 and 2006.

The city is governed by a mayor-council form of government. The city proper is also the "Capital Township" governmental entity. In addition, the government of the state of Illinois is also based in Springfield. State government entities located in the city include the Illinois General Assembly, the Illinois Supreme Court and the Office of the Governor of Illinois. There are three public and two private high schools in Springfield. Public schools in Springfield are operated by District No. 186. The economy of Springfield is marked by government jobs, which account for a large percentage of the work force in the city.

Springfield is located at 39.783250°N 89.650373°W. The city is at an elevation of 586 feet above sea level. Located within the central section of Illinois, Springfield is 90 miles northeast of St. Louis. The Champaign/Urbana area is to the east, Peoria, Illinois is to the north, and Bloomington/Normal is to the northeast.

Springfield's original name was Calhoun, after Senator John C. Calhoun of South Carolina. The land that Springfield now occupies was originally settled by trappers and traders who came to the Sangamon River in 1818. The settlement's first cabin was built in 1820, by John Kelly, its site is at the northwest corner of Second Street and Jefferson Street. In 1821, Calhoun became the county seat of Sangamon County; due to the fertile soil, and trading opportunities. Settlers from Kentucky, Virginia, and as far as North Carolina came to the city. By 1832, Senator Calhoun had fallen out of the favor with the public and the town renamed itself Springfield after Springfield, Massachusetts. At that time, Springfield, Massachusetts was comparable to modern-day Silicon Valley -- known for industrial innovation, concentrated prosperity, and the celebrated Springfield Armory. Most importantly, it was a city that had built itself up from frontier outpost to national power through ingenuity - an example that the newly named Springfield, Illinois, sought to emulate. Kaskaskia was the first capital of the Illinois Territory from its organization in 1809, continuing through statehood in 1818, and through the first year as a state in 1819. Vandalia was the second state capital of Illinois from 1819 to 1839. Springfield became the third and current capital of Illinois in 1839. The designation was largely due to the efforts of Abraham Lincoln and his associates; nicknamed the "Long Nine" for their combined height of 54 feet.

Lincoln arrived in the Springfield area when he was a young man in 1831, though he would not actually live in the city until 1837. He spent the ensuing six years in New Salem where he began his legal studies, joined the state militia and was elected to the Illinois General Assembly. In 1837 Lincoln moved to Springfield and spent the next 24 years as a lawyer and politician. Lincoln delivered his Lyceum address in Springfield. His farewell speech when he left for Washington is a classic in American oratory.

Winkle (1998) examines the historiography concerning the development of the Second Party System (Whigs versus Democrats) and applies these ideas to the study of Springfield, a strong Whig enclave in a Democratic region, mainly by studying poll books for presidential years. The rise of the Whig Party took place in 1836 in opposition to the presidential candidacy of Martin Van Buren and was consolidated in 1840. Springfield Whigs tend to validate several expectations of party characteristics as they were largely native-born, either in New England or Kentucky, professional or agricultural in occupation, and devoted to partisan organization. Abraham Lincoln's career mirrors the Whigs' political rise, but by the 1840s Springfield began to fall into Democrat hands, as immigrants changed the city's political makeup. By the 1860 presidential election, Lincoln was barely able to win his home city.

Winkle (1992) examines the impact of migration on political participation in Springfield during the 1850s. Widespread migration in the 19th-century United States produced frequent population turnover within Midwestern communities, which influenced patterns of voter turnout and office-holding. Examination of the manuscript census, poll books, and office-holding records reveals the impact of migration on the behavior of 8,000 participants in 10 elections in Springfield. Most voters were short-term residents who participated in only one or two elections during the 1850s, and fewer than 1% of all voters participated in all 10 elections. Instead of producing political instability, however, rapid turnover enhanced the influence of more persistent residents. Migration was selective by age, occupation, wealth, and birthplace. Therefore, more persistent voters were wealthier, more highly skilled, more often native-born, and socially more stable than nonpersisters. Officeholders were particularly persistent and socially and economically advantaged. Persisters represented a small "core community" of economically successful, socially homogeneous, and politically active voters and officeholders who controlled local political affairs while most residents moved in and out of the city. Members of a tightly knit and exclusive "core community," exemplified by Abraham Lincoln, blunted the potentially disruptive impact of migration on local communities.

The business career of John Williams illustrates the important role of the merchant banker in the economic development of central Illinois before the Civil War. Williams began his career as a clerk in frontier stores and saved to begin his own business. Later, in addition to operating retail and wholesale stores, he acted as a local banker and then organized a national bank in Springfield. He was active in railroad promotion and as an agent for farm machinery.

During the mid-19th century the spiritual needs of German Lutherans in the Midwest were not being tended. As a result of the efforts of such missionaries as Friedrich Wyneken, Wilhelm Loehe, and Wilhelm Sihler, this situation was remedied by the deployment of additional Lutheran ministers, the opening of Lutheran schools, and the creation in Ft. Wayne of the Concordia Seminary in 1846. The Seminary moved to St. Louis, Missouri, in 1869, and its practical division moved to Springfield in 1874. Through this seminary, during the last half of the 19th century and the first half of the 20th, the Lutheran Church Missouri Synod succeeded in serving the spiritual needs of Midwestern congregations by establishing additional seminaries, and by developing a viable synodical tradition.

The American Civil War made Springfield a major center of activity. Illinois regiments trained there, the first ones under Ulysses S. Grant, who marched his soldiers to a remarkable series of victories in 1861–62. The city was a political and financial center of support, and new industries, businesses, and railroads were constructed to help support the war effort. The war's first official death was a Springfield resident, Colonel Elmer E. Ellsworth.

Camp Butler, seven miles northeast of Springfield, Illinois, opened in August 1861 as a training camp for Illinois soldiers, but also served as a camp for Confederate prisoners of war through 1865. In the beginning, Springfield residents visited the camp to experience the excitement of a military venture, but many reacted sympathetically to mortally wounded and ill prisoners. While the city's businesses prospered from camp traffic, drunken behavior and rowdiness on the part of the soldiers stationed there strained relations as neither civil nor military authorities proved able to control disorderly outbreaks.

After the war ended in 1865, Springfield became a major hub in the Illinois railroad system and besides politics and farming, coal mining was a major industry for Springfield by 1900.

Local poet Vachel Lindsay's notions of utopia were expressed in his only novel, The Golden Book of Springfield (1920), which draws on ideas of anarchistic socialism in projecting the progress of Lindsay's hometown toward utopia.

The Dana-Thomas House is a Frank Lloyd Wright creation built in 1902–03. Wright began work on the house in 1902. Commissioned by local patron of the arts and public benefactor Susan Lawrence Dana, Wright's architecture harmonized with the owner's devotion to the performance of music. Coordinating art glass designs for 250 windows, doors, and panels as well as over 200 light fixtures, Wright enlisted Oak Park artisans. The house is a radical departure from Victorian architectural traditions and is the only historic site in Illinois acquired exclusively because of its architectural merit. Covering 12,000 square feet, the house contained vaulted ceilings and 16 major spaces. As the nation was changing, so Wright intended this structure to reflect the changes. Creating an organic and natural atmosphere, Wright saw himself as an "architect of democracy" and intended his work to be a monument to America's social landscape. It was opened to the public in September 1990; tours are available, 9:00 am–4 pm Wednesdays through Sundays.

Sparked by the alleged rape of a white woman by a black man and the murder of a white engineer, supposedly also by a black man, in Springfield, and reportedly angered by the high degree of corruption in the city, some of the white citizenry took their anxiety and frustration out on blacks. Rioting broke out on August 14, 1908 and continued for three days in a period of violence known as the Springfield Race Riot. Gangs of white youth and blue-collar workers attacked the predominantly black areas of the city known as the Levee district, where most black businesses were located, and the Badlands, where many black residences stood. Two blacks were lynched and four whites were killed by gunfire when black property-owners sought to defend their homes and businesses. The riot ended when the governor sent in more than 3,700 militiamen to patrol the city, but isolated incidences of violence against blacks continued in Springfield into September.