In the thirteenth century the coastal port and fishing town of Hartlepool became a fortified place with defensive walls constructed around the Headland. The defences were instigated by Robert Bruce the first, who was grandfather of the famous King of Scotland of that name. The Bruces acquired Hartlepool after the Norman Conquest although their period of ownership was characterised by disputes with the Bishops of Durham over who exactly owned the place. Some parts of Hartlepool’s town wall date from the 14th century including the historic Sandwell Gate which can still be seen. Here the wall is eight feet three inches thick. Hartlepool needed to be well defended as it was the chief sea port of the powerful Prince Bishops of Durham and was a regular target for Scottish and sea-borne attacks.
One notable Scottish raid on Hartlepool occurred in 1315, the year after King Edward I had been defeated by King Robert the Bruce at the Battle of Bannockburn. Robert the Bruce may have had a particular grudge against Hartlepool as it was the place to which the English King Edward had fled following the battle. Furthermore Robert the Bruce had once been the owner of Hartlepool, but it was confiscated from him by the English, when he was enthroned as King of the Scots
With thanks to David A Simpson