do you have a backup? if not request hosting guys to send you a backup. Most Hosting guys take daily/weekly and monthly backup.
here is a article on how to restore from database backup
https://codex.wordpress.org/Restoring_Your_Database_From_Backup
another helpful resource
https://codex.wordpress.org/Installing_WordPress
I am afraid the back up does not go back far enough. Any idea why this would occur
did you got it from your webhost? try getting older backup then. of some date before you updated to 4.1.1
Unfortunately webhost does not have a back up further than April 1. I updated on March 17
that is bad then, lookup if these website have your website cached.
web.archive.org/
archive.bibalex.org/
http://www.cachedpages.com/?page=privacy
for future setup backupbuddy or some similar plugin to backup every week
It is always a GREAT idea to backup by some form or another at least weekly if not daily. Sadly, most of the time, this is learned the hard way. I have personally had site completely lost.
The one thing I am interested in, is why you lost 6 months of content when you updated. What plugins did you have installed when you updated? As far as I know, WordPress does not touch much of the DB other than to update a few options and it even has checks to ensure that ever step of the upgrade meets some type of check before continuing.
