Setting Up Multi-Language Support in MediaWiki Using Translate Extension

'Multilingual MediaWiki' starts long before the Translate extension: core MediaWiki has a language system, and how you configure it decides whether the wiki works as one interlingual site or as awkward copy-pasted language islands. This guide covers the configuration path — core language settings, URL structure and the Translate extension — in the order you should implement it.

1. Core language configuration

MediaWiki can display in 400+ languages out of the box. Three core settings define the base:

$wgLanguageCode = 'en';              // the wiki's base content language
$wgLanguageFallbacks = [
    'nl' => [ 'en' ],               // what non-translated visitors see
    'sv' => [ 'da', 'en' ],
];
$wgDefaultLanguageCode = 'en';       // hmm — not a setting; see note

Correction to the common copy-paste: $wgDefaultLanguageCode is not a thing — the two settings that matter are $wgLanguageCode (base language of content, set at install) and $wgLanguageFallbacks (which language to display when a page has no translation in the reader's language). Interface language is per-user — Special:Preferences — so there is nothing to configure for that part.

2. URL structure: one wiki vs. per-language wikis

The big architectural decision, made before content work starts:

• One wiki, language prefixes in URLs — /wiki/Page, /wiki/de/Seite etc., via $wgLanguageCode + per-language URL implementation (the ULS and related extensions give the language switcher). Content lives with titles like Main Page/de (Translate's page translation uses language subpages) — everything shares history, users, categories and search
• Multiple wikis (one per language) — separate installations for en/de/fr; the choice of Wikimedia and large organizations with load concerns; costs duplicated infrastructure and cross-language linking

For most teams the single-wiki model with subpages is right: the Translate extension's page translation is built exactly for it.

3. The Translate extension and page translation

Install Translate (current versions require MediaWiki 1.46+), run the updater, and the multilingual machinery appears:

• Mark pages for translation — a translation administrator marks a prepared page; Translate splits it into units and offers them at Special:Translate
• Language subpages — translations are stored as Main Page/de, Main Page/fr, and language linking works automatically both ways
• No translation exists — readers get $wgLanguageFallbacks content or the base language, controllable per page

Details that matter in daily operation: keep templates and tables outside <translate> tags, mark pages for translation only after content stabilizes (source edits fuzz translations), and separate translator/reviewer groups as documented in the Translate configuration guide on this blog.

4. Language switcher and reader experience

• UniversalLanguageSelector — the compact language picker in the interface; also brings input methods and font support for CJK and other scripts
• Bilingual linking — with page translation active, interlanguage links are managed by Translate; manual [[de:...]] links should be removed to avoid conflicts
• Search — CirrusSearch (if you run it) handles language-aware analysis per page language; the default search per-language indexing is weaker but workable at small scale

5. Content strategy for actual multilingual operation

The configuration is the easy half; the workflow decides success:

• Stable source first — every English edit degrades existing translations; write, review, then mark for translation
• Priority languages — enable exactly the languages your community reads; 20 languages with 10% completion looks worse than 3 languages at 95%
• Statistics discipline — Special:LanguageStats weekly: which groups are behind, which languages are abandoned. Policy decisions follow the numbers

Done in this order — core language settings, URL model, Translate, language switcher, workflow — a wiki becomes genuinely multilingual instead of a set of parallel sites. The Translate help and the language manual close the remaining gaps.