Sandro N. answered 12/23/19
Singer, conductor and essayist giving Music History lessons
“The Four Seasons” is the name with which are usually known the first four concerts included in “Il cimento dell’armonia e dell’inventione” (“The Contest Between Harmony and Invention”), a set of twelve concerts for violin solo, strings and continuo, written by Vivaldi between 1723 and 1725, published in Amsterdam in 1725.
While the titles of the concerts — “La primavera”, “L’estate”, “L’autunno”, “L’inverno” — are by Vivaldi himself (which also wrote four sonnets, included in the score, which would match the musical description), “The Four Seasons” doesn’t appear in the score as a title, but has become an usual way to referring to them.
It’s worth to mention the fact that three more concerts in the collection carry descriptive titles given by Vivaldi: n. 5 “La tempesta di mare” (“The Sea Storm”), n. 6 “Il piacere” (“The Pleasure”) and n. 10 “La caccia” (“The Hunt”).