Q. How should I capitalize a foreign phrase within a title? For example, in sentence case, “The loi de position as a pedagogical norm.” I recall that an isolated non-English word would be capitalized (“The Loi as a . . .”), as would the first word in an included non-English title, but I can’t find anything regarding a phrase.
A. Except for any words that would be capped in the original language, both words and phrases in sentence-case titles can remain lowercase. The following titles from peer-reviewed journals illustrate this usage:
“The loi de position and the acoustics of French mid vowels,” by Benjamin Storme, in Glossa: A Journal of General Linguistics 2, no. 1 (2017): 64,* https://doi.org/10.5334/gjgl.300.
“Diachronic evolution of the subordinator kak in Russian,” by Natalia Serdobolskaya and Irina Kobozeva, in Linguistics 62, no. 3 (2024): 691–728, https://doi.org/10.1515/ling-2021-0213.
but
“Volk against Kaste: Nondemocratic popular sovereignty in Nazi Germany,” by Luna Sabastian, in Journal of Modern History 96, no. 4 (2024): 842–80, https://doi.org/10.1086/732675.
In that last example, the initial capitals in Volk and Kaste follow the rule for German nouns (see CMOS 11.42). Here are the same three titles in title case (usually preferred in Chicago style for the titles of works):
“The Loi de position and the Acoustics of French Mid Vowels”
“Diachronic Evolution of the Subordinator Kak in Russian”
“Volk Against Kaste: Nondemocratic Popular Sovereignty in Nazi Germany”
As the first example suggests, the non-English terms are in sentence case, according to which the first word and any other word that would normally be capitalized gets an initial cap. Alternatively, we could have applied title case to the French phrase:
“The Loi de Position and the Acoustics of French Mid Vowels”
You can do that if you know the parts of speech in the other language. In the title above, de remains lowercase as a preposition, but the nouns Loi and Position (which would normally be lowercase in a French title when not the first word) get initial caps. See also CMOS 11.28.
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* The number 64 is the article ID assigned by Glossa, an online-only open-access journal that isn’t paginated across issues in the traditional way (see CMOS 14.71 for more details). If you were to cite specific pages in a note (from the PDF version, which starts at page 1), you’d want to clarify what the numbers mean: “. . . (2017): pp. 3–4, article no. 64.”