Autumn is a second spring when every leaf is a flower.
Albert Camus

Why Autumn and Fall?

Before it was autumn and fall, it was harvest. While the modern names of winter and summer have been around for more than 1,000 years, the names of fall and spring are more recent—and less constant. This is partly because the two seasons were long viewed as secondary to summer and winter

Both spring and autumn used to go by different names. In the 12^th and 13^thcenturies, spring was called lent or lenten, while fall was called harvest. In the 14^th century things got a little chaotic. Lenten disappeared around the beginning of the 1300s, and the later lent similarly vanished only a few decades later. (It survives, of course, as the name for a religious observance.) By the end of the 14^th century there was no firm word for springtime: People referred to it as part of summer, they used Latin (ver) or French (primetemps), or they just made up new phrases. Harvest as a word to mean not just “a time of reaping” but also, even for city folk, “the third season of the year” lasted longer. But it was joined by autumn—a word borrowed from the French—by the 16^th century.

They each initially appeared in the 16^th century as spring of the leaf and fall of the leaf.

It’s a bit of a mystery why the superfluous autumn persists while analogous words like primetemps and ver have fallen out of use, but it may have something to do with the Atlantic Ocean. The rise of autumn and the appearance of fall happened around the same time as the British arrival on the American continent, and it’s there that the latter really caught on.