Treaties were generally expressed as lasting forever, with terrible oaths and promises of excommunication for any party which broke the treaty. Nevertheless, they were often broken before the ink was dry. In 1511, James IV requested Pope Julius to release him from the Treaty of Perpetual Peace with England, claiming that England had broken it numerous times. The Pope was not amenable, relying on England to divert French attention away from Italy.
Alliances were formed for a mixture of economic and political motives. After the Reformation, religious affiliations were also a factor – Scotland changed its long-standing relationship with Catholic France, to a closer one with Protestant England. However, France and equally Catholic Spain, continued to slug it intermittently for the next hundred years.