The New York Times Lab new tool called NYT Chronicle lets you graph the frequency of specific language was used in their newspaper over time; for instance, “World War I” vs. “Great War”:
Another revealing word comparison: “ladies” vs “women.”
UPDATE: Here’s a similar tool, the Google Ngram Viewer, a chart of search results in Google Books for the phrases ‘[first world war]’, ‘[the great war]’, ‘[World War I]’, 1800-2000 in English (suggested by commenter John Voss):
This is great. Another similar tool is the Google Books Ngram Viewer which I’m sure you’re also aware of. I just did a comparison of The Great War, WWI and First World War. I doubt it will let me embed it here, but here’s a link:
Google Ngram Viewer: ‘[first world war]’, ‘[the great war]’, ‘[World War I]’, 1800-2000 in English. https://books.google.com/ngrams/graph?content=first+world+war%2Cthe+great+war%2CWorld+War+I&year_start=1800&year_end=2000&corpus=15&smoothing=3&share=&direct_url=t1%3B%2Cfirst%20world%20war%3B%2Cc0%3B.t1%3B%2Cthe%20great%20war%3B%2Cc0%3B.t1%3B%2CWorld%20War%20I%3B%2Cc0
Thanks for the suggestion, John, added the Ngram embed you suggested to the post.