 To pay for it, he ruthlessly increased levels of taxation, while at the same time he ceased paying subsidies to the tribes north of the Danube that were vital for keeping the peace on the frontiers.Both decisions would have significant impacts upon the empire and his reign.In 245, Philip was forced to leave Rome as the stability established by Timesitheus was undone by a combination of his death, Gordian's defeat in the east and Philip's decision to cease paying the subsidies.