Confluence bundles a series of language packs. These languages are wrapped in language options in the ' Language Configuration ' interface. In the Confluence Administrator console, you can select choosing a default Language and set the user's own language options for user settings (Edit Your user Settings).
The following list of languages confluence can be supported after installation:
You can add additional language options to install the plugin by confluence. You need to have Confluence administrator privileges to install language packs in your confluence site.
Install a Language pack plugin
Use the Universal Plug-In Manager (Universal Plugin Manager) to install a language pack:
In the upper-right corner of the screen, click the console button , and then select the general Configuration link.
find the new plug-in in the left panel (find new add-ons).
Find the language pack in the Atlassian market.
Select Install to install the language pack.
Https://www.cwiki.us/display/CONF6ZH/Installing+a+Language+Pack
Confluence 6 Installing a language component