Vim supports installing help for multiple languages starting with version 6.2 and patch 299. The translations are available as separate packages.

Message translations are included with the normal distributions. Look for the "lang" archives on the download page

You can install the help files by unpacking the archive in the right place. To use it for all users unpack in $VIMRUNTIME/doc. For a personal installation unpack in your own vim directory. On Unix that is ~/.vim.

Language	contents	where to get it
Chinese	user manual and half the rest	On SourceForge
French	old translations based on Vim 6.2.017	On Github
German	Only a few files done	http://www.florianrehnisch.de/vimhelp/
Italian	User manual	https://sites.google.com/view/vimdoc-it/homepage
Japanese	User manual	http://vim-jp.org/vimdoc-ja/
Persian	Vim book, partly	http://www.isfahanlug.org/doku.php?id=vim
Polish	User manual	https://github.com/vvizzo/vim-doc-pl
Russian	User manual, rest is half complete	http://www.sf.net/projects/ruvim
Serbian	complete documentation	https://eevan78.github.io/vimdoc-sr/
Spanish	User manual partly translated	https://www.assembla.com/wiki/show/vim-doc-es
Swedish	Main help file help.svx	https://github.com/yeager/vimdoc-sv