Including

English and Old Irish, German, French, Hungarian, Czech, Albanian, Serbian, Rumanian, Swedish, Basque, Turkish, Mandarin Chinese, Japanese, Tagalog, Coptic, Egyptian, Hittite, and other dialects.
By the end of his life, he had studied the Bible in 26 languages, including Zulu, Swahili, Yoruba and Hausa.

At the Treaty of Locarno in December 1925, he was able to talk to every delegate of the League of Nations in their own language.