The name of Brus (Bruce) carries emotive overtones, associated as it is with Scotland's struggle for independence from English overlordship and the consolidation of its national identity. Yet for most of the two centuries prior to Robert Bruce's accession to the kingship of the Scots in 1306, the family was among the foremost of those many baronial houses which held lands on both sides of the Anglo-Scottish border, the ‘cross-border lords’ whose presence contributed in no small measure to the stability of the region and cohesion between the two kingdoms. Throughout these years the collateral lines of the Brus family, centred on Skelton in Cleveland and Annandale in south-west Scotland, were prominent to varying degrees in the politics of their day. Their involvement began around the year 1100, the starting-point of this study, with the arrival of the first Robert de Brus in England and his establishment by Henry I in what was to become a significant Yorkshire barony. Robert's holdings were subsequently extended north of the river Tees to include the region of Hartness, and further increased by his acquisition of Annandale from David I. Although the Yorkshire line of the family failed in 1272, the period covered by this study continues for a further twenty years until the time of the ‘Great Cause’ of Scotland, when the priorities of the Annandale Bruses shifted from their interests as Anglo-Scottish barons and became centred on their aspirations to the kingship.