Wullie, (Scottish Slang)
Wiriyamu, (Shona)
Whiriyamu, (Karanga)
Whiliyamu, (Ndebele)
Wilhelm (German, Polish, Swedish)
Willem, Wilhelmus, Wim, Pim, Jelle (Dutch, Frisian, Low German)
Wiremu (Maori)
Willelm (Old English)
Wellëm (Luxembourgish)
Walaam (Persian)
Cuglierme (Neapolitan)
Gilen, Guilen (Basque)
Gulielmus (Latin)
Guglielmo (Italian)
Guillaume (French)
Guildhelm (Old Dutch)
Guilhem Occitan)
Guillem, Guim (Catalan)
Guillén (Aragonese)
Guillermo (Spanish)
Guilherme (Portuguese)
Guillerme (Galician)
Gwilym (Welsh)
Gwilherm (Breton)
Gugghiermu (Sicilian)
Gllâome (Modern Norman)
Illiam (Manx Gaelic)
Uilleam (Scottish Gaelic)
Uilliam (Irish Gaelic)
Liam (Irish Gaelic)
Melhem (Arabic)
Gulielm (Albanian)
Уилиам - Uiliam (Bulgarian)
װֶעלװֶעל - /ˈvelvel/ (Yiddish)
Villem, Villu (Estonian)
Уильям - William, Вильям - William, Вильгельм - Vil'gel'm (Russian)
Вільгельм - Vil'hel'm (Ukrainian)
Vilhelm (Danish, Norwegian, Romanian, Swedish)
Vilhelmo (Esperanto)
Viliam (Slovak)
Viljem (Slovene)
ויליאם - /ˈviljam/ (older propronunciation), /ˈwiljam/ (contemporary) (Hebrew)
Vilim (Croatian)
Vilém (Czech)
Vilmos (Hungarian)
Viljams, Vilhelms, Vilis (Latvian)
Vilius, Viliumas (Lithuanian)
Viljami, Ville, Vilho, Viljo (Finnish)
Vilhjálmur (Icelandic)
Vilhjálmur, Viljam (Faroese)[6]
Vilhjálmr (Old Norse)
Vilyam, Vilyım (Turkish)
Vėljams (Samogitian)
Γουλιέλμος - Gouliélmos (Greek)
Γιλιαμ (Greek)
Գուլիելմոս - Goulielmós (Armenian)[7]
ウィリアム(Wiriamu) (Japanese)
威廉 (Wēilían Chinese), for persons whose original name is in English or German, for other languages there are other versions.