the most effective fighters for jacobitism were the supporting scottish clans, leading to an association of tartans with the jacobite cause. efforts to pacify the highlands led to the "dress act of 1746", banning tartans, except for the highland regiments of the british army. "[i]t was probably their use of it which gave birth to the idea of differentiating tartan by clans; for as the highland regiments were multiplied ... so their tartan uniforms were differentiated."