Supper was originally a secondary lighter evening meal. The main meal of the day, called dinner, used to be served closer to what is known as lunchtime, around the middle of the day, but crept later over the centuries, mostly over the course of the 19th century. When dinner was still at the early time, eating a lighter supper in the evening was very common. It was not always the last meal of the day, as there might be a tea later. Reflecting the typical custom of 17th century elites, Louis XIV dined at noon, with a supper at 10pm. Even when dinner was in the early evening, supper was served at, or on return from, a ball, and might be after other evening excursions. At an English ball in 1791, supper was served to 140 guests at 1:00am. They would all have had dinner at home many hours earlier, before coming out. Other, grander, balls served supper even later, up to 3:30 am., at a London ball given in 1811 by the Duchess of Bedford.
The modern usage of "supper" varies considerably. Sometimes supper is still used to describe a light snack or meal in the evening, either after or instead of dinner, but often it replaces dinner as the term for the main evening meal. Many people never use the term at all.
The distinction between dinner and supper was common in United States farming communities into the twentieth century, especially in the Mid-West and the American South, though today, most Americans consider the two synonyms and strongly prefer the term supper for the evening meal. During World War II, rations in the U.S. military were still divided into breakfast, dinner, and supper, using the traditional designations for meals.