That's exactly what I need (except CurrentUICulture instead of CurrentCulture :-).

Thank you very much.

I end with this code:

    private static void TrySetCulture()
    {
        string domain = HttpContext.Current.Request.Url.Host; //Host only
        if (TrySetCulture(domain)) return;

        domain = HttpContext.Current.Request.Url.Authority; //Host with port
        if (TrySetCulture(domain)) return;
    }

    private static bool TrySetCulture(string domain) {
        var uDomain = umbraco.cms.businesslogic.web.Domain.GetDomain(domain);
        if (uDomain == null) return false;
        System.Threading.Thread.CurrentThread.CurrentUICulture = new System.Globalization.CultureInfo(uDomain.Language.CultureAlias);
        return true;
    }

Petr

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