According to the CEO of Russian hacking tool creator Elcomsoft, Apple is storing Safari histories in the iCloud going back more than a year, possibly much longer, even where the user has asked for them to be wiped from memory.
Elcomsoft chief Vladimir Katalov told FORBES the iPhone maker kept a separate iCloud record, titled “tombstone,” in which deleted web visits were stored, ostensibly for syncing across devices.
Katalov told me he came across the issue “by accident” when he was looking through the Safari history on his own iPhone. When he took Elcomsoft’s Phone Breaker software to extract data from the linked iCloud account, he found “deleted” records going back a year. (Apple calls them “cleared” in Safari, not “deleted”).
http://www.forbes.com/sites/thomasbrewster/2017/02/09/apple-safari-web-history-deleted-stored-icloud