I'm having the same problem with my Ipad2. When I'm in Safari and go to my Bookmark, my History disappeared. It's no long first on
the list. But the icon clock that represents the Histroy is present on the bottom of the bookmark page. When I click it its always empty.
I've checked most of my settings. The only thing I did prior to losing it, was clearing history and cookies. It cleared it alright. But now I
cant monitor the sights of my kids and friends.