[galaxy-user] How can I get back a permanently deleted history?

Dear All, I'm working on Main and just deleted my history with all actual datasets and analyses instead of purging the deleted datasets. Is there a way to get it back? Is there a kind of backup? There were more than 1000 datasets in the history, a lot of workflows produced datasets that were further analysed and had to be purged to save diskplace. Then I unfortunatly clicked on delete permanently instead of purge deleted... Thanks, Thorsten