5.1.3.8 Latin Titles

Latin titles of ancient and medieval works should normally use sentence-style capitalization. Capitalize the first word of the title or subtitle, along with proper nouns and proper adjectives. Thus: De bello Gallico, De viris illustribus, and Cur Deus homo?

Renaissance and modern works, as well as English-language works with Latin titles, may usually be treated in headline style. Thus: Novum Organum and Religio Medici. If the date or category of a Latin title is uncertain, use sentence style as the safer default.

For further guidance, see CMS17, §8.158 and 11.54–59.