If, like me, you’re a bit off-put by Silverstripe’s tendency to put the default language of your site as en_US, or American English, you can override this pretty easily.
Simply put the following code into your mysite/_config.php, substituting en_AU for the language code of your choice. It’s almost too easy.
i18n::set_locale('en_AU');
This line will update the automatically generated meta language definition in your template, as well as facilitate multilingual sites should you require.