For as long as humans have looked to the sky and soil to predict upcoming events, almanacs have existed to help them. The word “almanac” itself dates so far back that no one can agree on its origin—guesses range from a Spanish Arabic derivation to a play on the Ancient Greek word for “calendar.”

With its roots in astronomy, early iterations of the almanac were calendars that charted moon phases and the rising and setting times of the sun. The Ancient Greeks and Egyptians included festival dates in their almanacs, while Romans pinpointed lucky and unlucky days to do business and Medieval versions added holy days.

Once the first printed version was distributed in Europe in 1457, their popularity became widespread. Starting in the 1600s, almanacs emphasized scientific developmen...