When organic geochemistry actually began as a recognized geoscience is a matter of definition and perspective. Constraints on its beginning are placed by the historical development of its parent disciplines, geology and organic chemistry. These disciplines originated independently and developed in parallel, starting in the latter half of the 18th century and flourishing thereafter into the 21st century. Organic geochemistry began sometime between 1860 and 1983; I argue that 1930 is the best year to mark its origin.