Why is coffee called a “cup of joe?”

A “cup of joe,” is one of coffee’s most common nicknames — and one of it’s most puzzling. Unlike “java,” which refers to a specific coffee-growing region, the origins of “cup of joe” are unknown. The term first started appearing in print in the 1930s, with the first occurrence of it in a book coming in 1936. Here’s a few theories, two historic and two linguistic, that might explain what gave rise to the term “cup of joe” at this time.

Martinson Coffee was Joe’s Coffee

Martinson Coffee has trademarked the term “cup of joe,” suggesting that the slang term comes from the company’s early years. Founded in New York in 1898 by Joe Martinson, who reportedly had a “bigger-than-life personality,” coffee may have locally been called “Joe’s coffee” or a “cup of joe.” As the company grew, “cup of joe” could have expanded from a local nickname to a more widely used term by the 1930s.

(Many people today aren’t familiar with Martinson Coffee, but the company is a classic: Andy Warhol liked to paint their cans, and, more recently, Martinson Coffee made an appearance on Mad Men in Season 2 Episode 7.)

Josephus “Joe” Daniels Banned Alcohol on Ships

In 1914, Secretary of the Navy Josephus “Joe” Daniels banned alcohol from all U.S. Navy ships. As this was close to the start of World War I, many young men would soon find themselves aboard a ship where the strongest drink available was coffee, or a “cup of joe.”

Those who argue against this theory often point out that this ban would have had little practical impact, because alcohol wasn’t widely available on U.S. Navy ships at the time. When boarding dry ships, though, men who were used to going to the local bar or having a drink at home would have felt the ban’s effects. Referring to coffee as a “cup of joe” would be one way to voice dissent and disapprovement without directly criticizing the Secretary of the Navy.

This theory doesn’t account for the twenty-year gap between Daniels’ ban and the rise of “cup of joe” in the 1930s. The term, however, may have fallen out of favor in the 1920s when sailors returned home, only to reappear during Prohibition in the 1930s.

Java + Mocha = Joe

Linguists sometimes argue that Joe could be a shortened version of Jamoke. Jamoke, which was a common nickname for coffee in the 1930s, was a combination of mocha and java. (Coffee drinkers today will still be familiar with mocha and java.) Jamoke could have been shortened simply to “joe,” a process that many slang terms go through.

The Average Man’s Drink

Since joe refers to an average man, “the average joe,” “cup of joe” could simply be a reference to an ordinary person’s drink. Regardless of whether this is the true origin of “cup of joe,” the term may have been kept alive by “joes,” or average guys, following World War II. As diners popped up in the 1940s and 50s, working men who ate their daily breakfast at these restaurants might have been served “cups of joe.”

No one knows for sure which of these four theories is the true account. All we know for sure is that the first recorded occurrences of “cup of joe” come from the 1930s, and the nickname is here to stay. In fact, it’s become much more popular since the 1980s.