Magnolia is a city in Columbia County, Arkansas, United States, that was founded in 1853. At the time of its incorporation in 1858, the city had a population of about 1,950. The city grew slowly as an agricultural and regional cotton market until the discovery of oil just east of the city in March, 1938, with the Barnett #1 drilled by the Kerr-Lynn Company. The Magnolia Oil Field was an important discovery, not just for the city but for the nation, as it was the largest producing field (in volume) during the early years of World War II, helping to fuel the American war effort. According to 2006 Census Bureau estimates, the population of the city is 10,478. The city is the county seat of Columbia County. It is also home to the World's Largest Charcoal Grill and the World Championship Steak Cookoff, part of the Magnolia Blossom Festival.