[3] Under the auspices of the Chicago, Milwaukee, St. Paul and Pacific Railroad (Milwaukee Road), Daniel W. Dame purchased 500 acres (200 ha), laid out the city of Lanark, and was elected its first mayor in 1861.

In 1886, 40 residents each donated one dollar to form a public library, and a primary and secondary school was completed in August 1871.

[4] Early in the Twentieth Century, Lanark was home to the Cotta steam car company.

[8] According to the 2021 census gazetteer files, Lanark has a total area of 1.12 square miles (2.90 km2), all land.

[9] Lanark is a part of Eastland Community Unit School District #308, which also includes Shannon and Lake Carroll.

Lanark, Shannon and Lake Carroll are the home of the Eastland Cougars.