# Passing language=british to biblatex-chicago with polyglossia

This question is similar to this one, except the crux here is biblatex-chicago.

I understand it's been a little rough building polyglossia support for biblatex. Thus far, biblatex-chicago has been tested for babel instead.

To achieve British localization in biblatex-chicago, the manual says to load babel with the option british. When I instead use polyglossia and \setmainlanguage[variant=british]{english}, however, it loads cms-american.lbx, in effect the same situation noted in this question. In this answer to that question, one of the solutions is to manually pass (in that case) language=ngerman to biblatex. Accordingly, the option language=british works for my purposes with biblatex. If this option is passed to biblatex-chicago, however, something seems to go amiss in the loading of the localization file, as all bibliography strings remain undefined:

\documentclass{book}
\usepackage{fontspec}
\usepackage{filecontents}
\usepackage[style=british]{csquotes}
\usepackage{polyglossia}
\usepackage[notes,language=british]{biblatex-chicago}

\setdefaultlanguage[variant=british]{english}
\setmainfont[Ligatures=TeX]{Cardo}
\begin{filecontents}{book.bib}
@online{key1,
title = {Stack Exchange},
url = {http://www.stackexchange.com},
urldate = {2014-09-16}
}
\end{filecontents}

\begin{document}

See date formatting in footnote below.\autocite{key1}

\end{document}


Warnings returned:

Package biblatex Warning: Bibliography string 'urlseen' undefined
(biblatex)                at entry 'key1' on input line 21.

Package biblatex Warning: Bibliography string 'september' undefined
(biblatex)                at entry 'key1' on input line 21.


Output:

(source: langeslag.org)

If I load ngerman instead it actually works, though obviously with the wrong localization. This suggests that british fails to be tied to a localization file.

I can think of a couple of workarounds:

1. Opt for biblatex over biblatex-chicago and copy the relevant contents of biblatex-chicago.sty into my own preamble (as well as importing the contents of biblatex-chicago's cms-british.lbx somehow -- what's the elegant way of doing this?);
2. Swap out polyglossia in favour of babel. Note that my document contains over a dozen European languages.

But what's the correct way of actually telling biblatex-chicago to load the localization from its own cms-british.lbx?

You can make biblatex-chicago into thinking that the language is indeed british:

\begin{filecontents}{\jobname.bib}
@online{key1,
title = {Stack Exchange},
url = {http://www.stackexchange.com},
urldate = {2014-09-16}
}
\end{filecontents}
\documentclass{book}
\usepackage{fontspec}
\usepackage{filecontents}
\usepackage[style=british]{csquotes}
\usepackage{polyglossia}
\setdefaultlanguage[variant=british]{english}

\let\keptlanguagename\languagename
\def\languagename{british}
\usepackage[notes,language=british]{biblatex-chicago}
\let\languagename\keptlanguagename

\setmainfont[Ligatures=TeX]{Cardo}

\begin{document}

See date formatting in footnote below.\autocite{key1}

\end{document}


Proper support of polyglossia would require changing biblatex-chicago.sty.

Afaik, the polyglossia definition of the UK variant is

\setdefaultlanguage[variant=uk]{english}


so try changing the line

\setdefaultlanguage[variant=british]{english}


Hope it helps! Jigdrel