Cumnock housed many miners, and also served as the market town for the other, smaller towns in the district, like Auchinleck, Ochiltree, Lugar, Muirkirk and New Cumnock (parts of which, incidentally, are said to be older than Cumnock)
The town has a strong socialist heritage due to its role as a mining centre. The father of the Labour Party, James Keir Hardie, lived in the town for a large part of his life, and a statue to him sits outside the town hall. A small housing scheme in the town (Keir Hardie Hill) is named after him. The popular left-wing politician Emrys Hughes was local MP for a time in the mid-20th century, and also lived in the town.
William Wallace allegedly lived in Cumnock for a short time, according to the book, The Wallace, by Blind Harry. Cumnock is also in the heart of Robert Burns country and the poet is said to have spent time there.
As it lost its railway station and local industries declined in the later 20th century, Cumnock's economy suffered badly, and for a time it seemed to be destined to become a ghost town. A rising crime rate, problems with drug addiction and related social problems in the area, together with the high unemployment rate in the district and in Cumnock in particular, all added to this atmosphere of despair. In more recent years however things have looked brighter. With a new road development providing a faster link to Kilmarnock and Glasgow, it seems to be becoming something of a commuter town, with new modern housing developments appearing in the suburbs, such as the Holmhead area, and on the periphery of the Barshare housing estate (scheme).
Cumnock also has one of Scotland's biggest Junior football teams, Cumnock Juniors. Though attracting big attendances and spending large sums of money in pursuit of success, they have been overshadowed by the achievements of local rivals Auchinleck Talbot, from the adjacent town.
For many years there were two secondary schools, Cumnock Academy and Saint Conval's High School - which was later annexed with St Joseph's Academy in Kilmarnock and became known as St Joseph's Cumnock Campus. In 2004 however St Joseph's Cumnock Campus was shut down due to falling attendance figures, and the town's Catholic children now attend the original St Joseph's Academy in Kilmarnock.