date_i18n localization not working

I’m having an issue using the date_i18n localization function for dates. Specifically I have my WordPress set to the ‘fr_FR’ locale but the dates it’s spitting out are in English. I believe my locale files and config files are set up properly as my administration panel is displayed properly in French. I checked the .po file and it does contain the proper translations (i.e. January -> janvier).

Here’s a snippet of how I’m using it:

<span><?php _e('Posted on', 'my.domain'); ?> <?php echo date_i18n( 'l F jS, Y', time() ); ?> ?></span>

(I’m aware this will print the current time not the post time).