The highway is named in honour of the explorer and botanist Allan Cunningham who followed a route close to where the modern-day highway runs. In 1828 after discovering the route Cunningham sent a report to Governor Ralph Darling emphasising the economic benefits that a link between the coast and pastoral lands of the Darling Downs would provide. The first road between the coast and the Darling Downs was Spicers Gap Road developed in 1859, which crossed the range at Spicer's Gap and was suitable for the drays used at that time. Although Cunningham's Gap was known at that time, it was considered too steep a route for drays. With the opening of the Southern railway line between Toowoomba and Warwick in 1871, passenger and goods transport switched to the railways and Spicers Gap Road fell into disuse and was not maintained well due to the cost.