County adjacent to Indianapolis-Marion County on the west and part of the Indianapolis Metropolitan Statistical Area. In 1820 the families of Bartholomew Ramsey, Harris Bray, John W Bryant, James Dunn, and Ezekiel Moore settled along the White lick River in what is now Hendricks County. They came to the area by the Terre Haute Trail, a path that led to settlements along the Wabash River. Soon Hendricks County had a population of over 1,000. The county, organized in 1824, chose Danville, near its geographic center, as the county seat, opening a courthouse there in 1826. The land in northeastern Hendricks County was swampy and uninhabitable, but the rest of the county had been settled by 1840.

The Cumberland Road, later called the NATIONAL ROAD, came through the southern part of the county in 1830 and contributed to the rapid settlement and development of that area. Businesses established along the National Road served the constant stream of travelers and hog drovers. By the late 1830s, 150,000 hogs passed through Hendricks County annually. Residents profited from these drives by operating stock stands and renting rooms to travelers. In 1839 the Quakers who originally settled the area platted the town of PLAINFIELD on the National Road in the southeastern part of the county. The small town quickly became an important Quaker center, and the Western Yearly Meeting of Friends was established there in 1858 to serve Quakers in northwestern Indiana and Illinois. In the 1840s Hendricks County citizens hired a group of Irish immigrants to drain the swampy land in the northeastern townships. The workers constructed wood-lined ditches employed in their native land to channel water off the land. The area was quickly transformed into excellent farmland and soon was traversed by railroads and interurbans. The Indianapolis and Terre Haute Railroad, also called the Vandalia Line, connected Plainfield to Indianapolis in the 1880s and provided Guilford Township farmers with easy access to Indianapolis STOCKYARDS. Four interurban lines provided Hendricks County residents easy access to Indianapolis in the early 1900s, and area farmers used the interurbans to ship livestock and produce to markets all over the Midwest.

The completion of the Indianapolis and St. Louis Railroad through Danville in 1880 spurred economic growth in the county seat. In 1878 ambitious Danville citizens lured Central Normal College from its home in Montgomery County. The school grew steadily in Danville, peaking at 1,500 students in the late 1890s. Central Normal College continued with enrollments over 1,000 through the first quarter of this century; but its fortunes declined shortly before World War II. The school went bankrupt and closed its doors in 1951.

In the early 1990s Hendricks County (population 75,717) changed from a rural-agricultural to a suburban area. As Indianapolis expanded after World War II, suburban tracts developed throughout the eastern half of the county. Danville, once the largest town in the county, has not grown as quickly as its neighbors to the east. It had 4,345 residents in 1990 compared to 7,628 in Brownsburg, historically a smaller and less important community. In 1990 Plainfield was the largest town in Hendricks County with a population of 10,433.