The Great Man - Sir Robert Walpole, Scoundrel, Genius and Britain's First Prime Minister
Edward Pearce, Jonathan Cape, 2007, £25

Edward Pearce famously reinvented himself after years of contributing to the Daily Express and The Telegraph through a single brilliant mea culpa article in "Encounter" setting out why he had changed his mind and now believed the Falklands War to have been a grave error. Since then, via a number of hilarious books of parliamentary sketches, he has increasingly turned to weighty historical and biographical tomes.

He has now given us the first modern biography of Robert Walpole, Britain's first acknowledged Prime Minister. It is a worthwhile task worthily accomplished and researched in considerable depth. Edward Pearce's skills as a parliamentary sketch writer enhance the raciness of the narrative which leaps from the South Sea Bubble to political intrigue, with the dishing of the Tories, the thwarting of Jacobite rebellions - potential and real - and the remarkable tactics used to maintain himself in office.

Pearce's homework serves Walpole's monarchs well. At a time when government ministers depended more on royal patronage than on open parliamentary support, Pearce sets out Walpole's skilful wooing of George I and the growing friendship with his wife, the Queen Caroline, which enabled Walpole to remain in office after the first George's death in 1727. Despite his early antipathy to Walpole, George II grew to depend more and more on his de facto Prime Minister.

Pearce's research gives us a very different slant on George I, the "German king", than the received truth. George could speak and write English, certainly from early on in his reign, and was a more concerned and sympathetic sovereign than the usual picture of him as a cold and distant monarch.

Despite his avowed antipathy to the South Sea scheme, Walpole himself had bought a modest number of shares and was only saved from more serious damage by the apparently deliberate tardiness of his lawyer who harboured wise doubts on the viability of the scheme. According to Pearce, King George was also involved and was grateful to Walpole's oratory which lightened the odium into which he was slipping amongst public opinion.

There is a tendency amongst those of us whose parliamentary history starts with the great Reform Act of 1832 to regard earlier parliaments of no consequence. In fact, of course, the epic struggle between King and Parliament had been resolved in favour of the Commons almost two centuries earlier. Edward Pearce pays due regard both to the corruption of seats being at the disposal of wealthy patrons and to the importance of the electorate in many towns.

One often unnoticed consequence of the undemocratic system was the arrival in parliament of youthful MPs. Walpole himself was elected at the age of 25, inheriting the East Anglian seat of Castle Rising from his father. The following year he transferred to the more important borough on Kings Lynn which he represented for forty years.

Walpole lived in an age of marriage alliances and expeditionary forces. Pearce skilfully weaves the warp and the weft of the dilemma facing Walpole between the bellicose consequences of marriage alliances and his almost obsessive determination to keep England out of foreign wars - a policy it has to be said greatly assisted the economic strength of Britain even though "he had become a spectator to the creation of power, lands and aggressive assurance for the French state, the prevention of which had been the preoccupation of British, and especially Whig, opinion for fifty years."

With resonances of today's politics, it is clear that Walpole stayed in office too long. Eventually he dragged out his demise interminably, like Callaghan in 1979, seeking to drag sick and disenchanted MPs to the House to vote to save him. It was all to no avail, the key vote was lost by sixteen, and on 3rd February 1742 Britain's first Prime Minister realised his twenty-one year term of office was at an end.

So far, so good. Edward Pearce's formidable efforts have given us a powerful narrative and a valuable reference work, but it is not without its defects. It feels as if it is written for the already knowledgeable reader rather than to captivate the not yet convinced amateur lover of history. Pearce has so immersed himself in the multiple connivances, plots and politics of the early seventeenth century that he seems to forget that many prospective readers will need a glimpse of the over-arching structure before plunging into the rapids below. It is particularly difficult to keep track of the considerable number of participants in the story and a "dramatis personae" of the key players would be a great boon.

That said, this is undoubtedly a valuable contribution to the understanding of a key period of British political transition, even if it does take a certain amount of concentration to make the most of it.