Before refrigeration, all apple cider was hard cider. Apples crushed to the point of releasing their juices quickly become a fizzing, cloudy fermented brew. What we think of as apple juice had a limited lifespan – drink it now or face it’s alcoholic dark side.
But that was okay because most people wanted cider. Cider was the drink of choice for men, women, and children for centuries. It was easy to make at home and provided a way for families to store the apple harvest without spoilage. Cider was also safer than water in many places, and could be made into vinegar for preserving vegetables and fruits for the winter. It really was a useful liquid.
Apple juice only became common with refrigeration in the late 19th and early 20th centuries. The sweet juice was helped along by temperance advocates who decried the dangers of drinking fiendish cider, demon rum’s evil, fruity cousin.
Americans only began calling alcoholic cider “hard” in the 20th century when the sweet juice ascended to the apple drink of choice. Today, cider and apple juice are used almost interchangeably in the United States (some people do have specific beverages in mind with each word but there’s no consensus on what each mean), while alcoholic apples get the moniker “hard.” In most other countries, cider – without qualifiers – still refers to fermented apple juice.