England and Scotland to form the United Kingdom in 1707,2 and that between the United Kingdom and Ireland (of which Northern Ireland’s pres ence in the UK is the remaining legacy) in 1800.3 This self­ conscious pro cess of creating a plurinational union has not been untroubled by polit ical upheaval, most evid ent in the Irish cam paign for inde pend ence which led to the partition of Ireland in the 1920s and the ensuing dispute over the consti tu tional status of Northern Ireland. Relations in other parts of the UK have been more amic able, but even so, since the 1950s there has been a revival in Scottish and Welsh nationalism4 that has led in the late 1990s to the cre ation of devolved gov ern ment in each of these three ter rit ories. These de velopments represent a degree of consti tu tional change and re cog ni tion of the UK’s national diversity un pre ced en ted since the very pro cesses of union themselves. And today, therefore, devolution to Scot­ land, Wales and Northern Ireland serves to institutionalise further than ever before the national plur al ism of these islands, adding a soph istic ated gov ern­ mental ap par atus to the sociological reality of the UK as a ‘union state’.5 Although the idea of the UK as a union state em braces also the status of Wales, Northern Ireland and other island ter rit ories, for the purposes of this chapter we are prim arily concerned with the Anglo­ Scottish Union which in the eyes of many remains the founda tional consti tu tional moment in the cre ation of the British state. The marriage of Scotland and England was completed by the Union of the Parliaments of these two coun tries in 1707 which was the culmina­ tion of the pro cess since the union of the crowns in 1603. The consti tu tional significance of this pro cess from the per spect ive of plurina­ tionalism is that Scotland and England came into the union with very different consti tu tional traditions. The seven teenth century was marked by brutal civil war and in this time a doctrine of rebellion within the Scottish body politic emerged that was gen erally more rad ical than the more con ser vat ive consti tu tional tradi­ tion that can be seen in English consti tu tional his tory. This is par ticu larly notable in the rebellion of 1688-1689 that resulted in William and his wife Mary acced­ ing to the thrones of the two states (William III and II r. 1689-1702 and Mary II r. 1689-1694). The revolu tion not only hastened the road towards full union, but also served to highlight how Scotland and England would each come into this union bringing with them very different consti tu tional traditions. In the revolu­ tion of 1688-1689 it was clear that Scotland and England had different visions of the legal position of the mon arch. In England, there was a strong attempt to deny that what was occurring was in fact revolu tion. The Convention Parliament which was called without the authority of the existing King (James II and VII r. 1685-1689), and hence illegally (by consti tu tional law the English Parliament could not convene without the King), instead of declaring this to be an act of legitimate, if technically illegal, revolt, instead declared that the throne was vacant and offered it to William and Mary. The Scottish Parliament by contrast was openly revolu tionary. Since there was a strong consti tu tional tradition of limited mon archy including the widely held understanding that a king could be ejected from the throne, rather than argue that James had left the throne vacant in 1688, the Claim of Right issued by the Parliament in Scotland, stated

expli citly that James had forfeited the throne of Scotland. This unambiguous declaration that the Scottish Parliament could depose a king who acted in a grossly unconsti tu tional way gave new impetus to a freshly invigorated Parlia­ ment in the 17 years between the Claim of Right and the Treaty of Union.6