Often confused, Afternoon Tea and High Tea are actually not the same.
Afternoon Tea started in the mid-1840s when the Duchess of Bedford, Anna Maria Russell, invited her friends for a light meal of tea and cakes. This was meant to fill in the long gap between lunch and dinner which was then served between 7:00- 8:30 pm. Quickly, Afternoon Tea became a social event for the British upper class.
On the other hand, High Tea started with the working class during the Industrial Revolution. Working in factories considerably far from their homes, factory workers returned home very hungry in the early evening. The after-work meal then had to be more filling. Aside from tea, the meal included bread, vegetables, cheese, pies, sometimes meat and dessert.
Why was this meal called "High Tea" then? One common explanation given was because the meal was served on the dining table while seated on high back dining chairs. Afternoon Tea, in comparison, was served on low tables while seated on low, comfortable chairs or sofas. For which reason, Afternoon Tea is also referred to as "Low Tea."