At one level Great Britain at the beginning of the 18th century was like the Christian doctrine of the Trinity, both three and one, and altogether something of a mystery.

In the last quarter of the 20th century, Britons have been understandably obsessed with the problem of having too little power in the world. In the third quarter of the 18th century, by contrast, their forebears were perplexed by the problem of having acquired too much power too quickly over too many people.

These developments - a massive transfer of land by way of inheritance and purchase, an unprecedented rise in the profitability of land and increasing intermarriage between Celtic and English dynasties - helped to consolidate a new unitary ruling class in place of the more separate and specific landed establishments that had characterised England, Scotland, Wales and Ireland in the Tudor and Stuart eras.

Most Britons still lived and died without encountering anyone whose skin colour was different from their own. Slaves, in short, did not threaten, at least as far as the British at home were concerned. Bestowing freedom upon them seemed therefore purely an act of humanity and will, an achievement that would be to Great Britain's economic detriment, perhaps, but would have few other domestic consequences.

Chilvalry's essential function, Maurice Keen has written, is always to hold up an idealised image of armed conflict in defiance of the harsh realities of actual warfare. By definition, chivalry also reaffirms the paramount importance of custom, hierarchy and inherited rank.

It would be wrong to interpret the growth of British national consciousness in this period in terms of a new cultural and political uniformity being resolutely imposed on the peripheries of the island by its centre. For many poorer and less literate Britons, Scotland, Wales and England remained more potent rallying calls than Great Britain, except in times of danger from abroad. And even among the politically educated, it was common to think in terms of dual nationalities, not a single national identity.

In virtually every Continental state at this time, aristocracies had to live with the risk that their property might be pillaged or confiscated. Only in Great Britain did it prove possible to float the idea that aristocratic property was in some magical and strictly intangible way the people's property also. The fact that hundreds of thousands of men and women today are willing to accept that privately owned country houses and their contents are part of Britain's national heritage is one more proof of how successfully the British elite reconstructed its cultural image in an age of revolution.