From the ArcaMax Publishing, The Culinary World, with Chef James Newsletter:
http://www.arcamax.com/news/chefjames/s-335325-220460
Chewing gum as we know it today may be an American invention, but
humans have been chewing various gums, resins and latex secretions of
plants for thousands of years. Mastic gum has been chewed by
Mediterranean peoples for thousands of years, and Native Americans
chewed the resin from spruce trees. The first commercial chewing gum,
State of Maine Spruce Gum was introduced in 1850. It was made using
spruce tree resin, which had a harsh taste and tough texture. (I
believe it is still available in northern New England). In 1871 Thomas
Adams patented chicle gum, with sugar and sassafras flavoring. It had
the right chewing properties with no harsh taste or texture, and it
caught on quickly with the American public. This was soon followed (by
other companies) with peppermint flavored gum in 1885, Chiclets (gum
with a hard sugar coating in 1900, Juicy Fruit and Spearmint flavors
in 1893, and finally bubble gum in 1928.
Courtesy of FoodReference.com.