Changing the Default Language Context in a Babel-Based Site

Changing the default language on an existing multilingual site sounds simple until you realize how many assumptions the project may already have about the current primary context.

The practical problem

A site already has two languages, for example ru and lt. Russian is currently the default. The goal is to make Lithuanian load first without rebuilding the project from scratch.

What needs to be reviewed

• which context or root branch the site treats as canonical
• how the language switcher builds URLs
• whether templates or snippets hardcode assumptions about the current default language
• whether sitemap, hreflang, and redirects rely on the old primary language

The safe way to do this is not to “flip one switch and hope.” First map all places where the primary language affects routing, then change the default flow deliberately.