Adams County lies in northeastern Indiana in the United States and shares its eastern border with Ohio.

[4] The county has four incorporated cities and towns with a total population of over 15,000,[5] as well as many small unincorporated communities.

[10] The statute that mandated the creation of this county was passed on February 7, 1835, and the organization itself was authorized on March 1, 1836.

[12] The first non-Native settlers arrived in what is now Adams County in 1835, encouraged by the new Erie Canal and by the end of the Black Hawk War.

These were "Yankee" settlers, that is to say they were descended from the English Puritans who settled New England in the colonial era.

They were primarily members of the Congregational Church although due to the Second Great Awakening many of them had converted to Methodism and some had become Baptists before coming to what is now Adams County.

U.S. Route 27 continues south through the town of Monroe, near the center of the county, and then on through Berne and Geneva.

Its Köppen climate classification is Dfa,[21] meaning that it is cold, has no dry season, and has a hot summer.

Manufacturing employees the most employed residents at 31.2%, followed by 17.6% in education, health care and social services, and 10.3% in retail.

[46] Indiana State Road 116 runs west–east across the county, from Bluffton southeast to Linn Grove, south to Perryville, then east to a terminus at U.S. Route 27 in Geneva.

[47] Indiana State Road 218 runs west–east across the southern end of the county, passing through Berne.

[48] CSX Transportation operates a rail line from Decatur, running northwest toward Fort Wayne.

The council members serve four-year terms and are responsible for setting salaries, the annual budget and special spending.

This board executes the acts of the council, causes necessary revenues to be collected, and manages day-to-day functions of the county government.

This court's judge is elected to a term of four years and must be a member of the Indiana Bar Association.

[50] The county has other elected offices, including sheriff, coroner, auditor, treasurer, recorder, surveyor and circuit court clerk.

[50] Each township has a trustee who administers rural fire protection and ambulance service, provides poor relief, and manages cemetery care.

The Diocese of Fort Wayne and Lutheran Schools of Indiana both operate in Adams County as well.