1) Coca-Cola was invented in 1886 by pharmacist John Pemberton as a patent medicine containing cocaine and caffeine. (2) It grew to become America's best known brand but faced increasing competition from imitators in the early 20th century and Pepsi in the 1930s. (3) Pepsi's "twice as much for a nickel" campaign in the 1930s successfully challenged Coca-Cola's bottle size advantage, gaining market share during the Great Depression.