Robert May, an advertising copywriter for Montgomery Ward, thought up Santa’s most trusty reindeer in 1939.

That Christmas, the department store wanted their in-house Santa Claus to give free souvenirs to shoppers, hoping that the company-branded keepsake would remind them of Montgomery Ward long after returning home. Robert May hatched an idea to distribute a free Christmas-themed poem to customers, and he got to work writing the now-iconic verses for “Rudolph the Red-Nosed Reindeer,” though he originally considered other names for the character, including “Reginald” and “Rollo.”

Eventually, the poem was put to music and famously recorded in 1949 by Gene Autry, the “Singing Cowboy, ” well known for starring in Western musical films. With 12.5 million copies sold, Gene Autry’s rendition remains the runner-up for the most popular record of the 1940s, but his song never approached the 50 million sales reached by Bing Crosby’s 1942 version of “White Christmas,” the best-selling single of all time.