From wikipedia:

Lum and Abner, an American radio comedy which aired as a network program from 1932 to 1954, became an American institution in its low-keyed, arch rural wit. One of a series of 15-minute serial comedies that dotted American radio at its height as America's number one home entertainment—others included Amos 'n' Andy, Easy Aces, The Goldbergs, and Vic and Sade—Lum and Abner included various elements of each but yielded something as singular as the others and became somewhat more of an institution.

Lauck and Goff had known each other since childhood and attended the University of Arkansas together (joining the Sigma Chi Fraternity together while there). They performed locally and established a blackface act which led to an audition at radio station KTHS in Hot Springs, Arkansas. Prior to the audition, the two men decided to change their act and portray two hillbillies, since there were already an overabundance of blackface acts at the time. After only a few shows in Hot Springs, they were picked up nationally by NBC, and Lum and Abner, sponsored by Quaker Oats, ran until 1932. Lauck and Goff performed several different characters, modeling many of them after real-life residents of Waters, Arkansas.

After the Quaker contract expired, Lauck and Goff continued to broadcast over two Texas stations, WBAP (Fort Worth) and WFAA (Dallas). In 1933, Ford Motor Company became their sponsor for approximately a year. Horlick's Malted Milk, the 1934-37 sponsor, offered a number of promotional premium items, including almanacs and fictional Pine Ridge newspapers. During this period, the show originated from Chicago's WGN (AM), one of the founding members of the Mutual Broadcasting System. In 1936, the city council of Waters changed the town's name to Pine Ridge.[1] Postum cereal sponsored Lum and Abner in 1938-39, before Alka-Seltzer picked up the duo for eight years. Over the course of its life, Lum and Abner appeared on all of the major radio networks, CBS and ABC (formerly NBC Blue), in addition to NBC and Mutual.