None of the native Indians remain, although some descendants of the earliest European settlers claim partial ancestry.

The first European contact was by French explorers in the seventeenth century, travelling southward down the major rivers.

The main European settlement was from the southwest, as people moved inland from the established transportation route of the Mississippi River.

[3] It was formed out of Greene and Madison Counties and was named after Macoupin Creek,[4] which runs near Carlinville and meanders southwest to the Illinois River.

The greatest change was in the building of railroads, and Macoupin County was on the rail and road transportation link between St. Louis and the still-young metropolis of Chicago.

Towns were small and sparsely distributed, and any new communities were founded along the railroad lines that provided transportation.

Agriculture remained a mainstay of the economy, but this was joined by coal mining, an industry that partially changed the complexion of the county.

Macoupin County was often at the center of major labor disputes between mine owners and miners and was a hotbed of union activity.

The county had previously played a significant role in violent 1890s disputes that brought unwanted national attention, was at center stage when the United Mine Workers rose to power, and was again prominent during the internecine war between the UMW and the Progressive Miners of America of the 1930s.

The twenty-first century has seen a major change in these voting patterns due to the county's conservative population.

The 2012 election saw Illinoisan Barack Obama become the first Democrat to win the presidency without carrying Macoupin County, and in 2016 Hillary Clinton won less than thirty percent of the vote in this once traditionally Democratic county – a figure eleven percent worse than McGovern's in his landslide defeat.