When did Caesar's works begin to be used to teach Latin to non-native speakers?

Question

Eleanor Dickey, a professor of Classics, responded recently to a question about the works read by those learning Latin as a second language in the Greek-speaking ancient world:

[Students in the East] start on Virgil (mainly the Aeneid) and Cicero (mainly the Catilinarians) and then read Terence, Sallust, Seneca’s tragedies, and Juvenal. Caesar is conspicuous by his absence. [emphasis added]

That last sentence is intriguing, since Caesar's works play such an important role in modern Latin instruction.

When did the works of Caesar, like the Commentarii de Bello Gallico, begin to be used widely for Latin language instruction among non-native speakers?

Answer 1

I am uncertain of the earliest, but Thomas Jefferson often wrote to younger men he mentored that it should be included in their personal reading lists (see for example a letter to Peter Carr), so presumably at least as early as the later half of the 18th century.

Answer 2

I am not able to say “when” exactly Caesar’s De bello Gallico became the first book foisted onto juvenile learners of Latin, but I suspect it was not long ago. In the 19th century and the first part of the 20th Caesar was certainly at the top of the Latin curriculum, and Xenophon’s Anabasis was the first book on the Greek syllabus. It is surely no coincidence that both of these books are all about war and conquest. Today I think most learners of classical languages find Caesar and Xenophon much less interesting than Horace, Catullus, Ovid, Homer, Plato or Sophocles. Tastes change.