If there is no internet connection, which language else I could choose to use Ubuntu localized.
Many languages are available on a DVD edition (not CD) of Ubuntu. You have to check the manifest of the version you want.
For example, for Ubuntu 12.04.2 64bit, the manifest is here.
When you open the page, click the search button of your browser (Firefox=F3) and write:language-pack, then click on Highlight all and you will see which languages are available on the DVD.