Sporadic warfare and cattle raids were regular features of the Borders during the Middle Ages, especially during the late 13th and early 14th centuries (see also pele‐towers). After their victory at Bannockburn (1314) Scots armies penetrated deep into the six northern English counties. An enquiry into the devastation they had caused in 1318 revealed that 140 of Knaresborough's 160 houses had been burnt. This was the most serious invasion before that of 1745. Henry VIII (r. 1509–47) waged several wars against the Scots. The defences of Berwick‐upon‐Tweed were a major preoccupation throughout the 16th century. The union of the two Crowns under James I of England and VI of Scotland in 1603 brought peace. The two countries were formally united in 1707, but Scottish support for the Jacobite cause brought renewed tension, culminating in the invasion of Bonnie Prince Charlie's Highlanders in 1745 and their defeat at Culloden the following year. See Linda Colley, Britons: Forging the Nation, 1707–1837 (1992).