Iron Kingdom: The Rise and Downfall of Prussia, 1600-1947

by Christopher Clark

816pp, Allen Lane, £30

Rumours emanating from the publishing world suggest that, with the possible exception of books about queens, the "history boom" of recent years has already gone into steep decline. Let us hope that the sands into which it has run are not those forming the soil of Brandenburg around Berlin. For it is on this unpromising terrain that Christopher Clark's excellent tome begins.

Landlocked and without defensible frontiers, medieval Brandenburg hardly seemed predestined to become "the heartland of a powerful European state". In 1417 the territory, which constituted one of seven electorates of the Holy Roman Empire, was bought by Frederick Hohenzollern, who established himself as Frederick I. Though far from powerful in that early period, the Hohenzollerns held Brandenburg together, avoiding break-up and partition at moments of succession, maintaining their neutrality in surrounding disputes, and introducing Protestant reformation at a tactfully gradual pace.

Things were interrupted by the thirty years war (1618-48), when the German lands became the site of devastating conflict between the Habsburg emperor and Protestant forces that included Denmark, Sweden, Spain and France. The extortion, slaughter and torment introduced by the warring armies as they swept back and forth would be remembered for centuries. Historians have blamed it on the weakness of Elector George William, but Clark insists that he was faced with a "structural" challenge that would weigh on many future Berlin governments, which also found themselves "stranded between the fronts" of Europe's conflicting powers.

It was a different Frederick, this one known as the "Great Elector", who restored Brandenburg after the war. He secured his domain by raising a carefully trained army that answered to his newly established state rather than to the provincial aristocracy. He also entered a carefully chosen series of alliances, which shifted to reflect the balance of power between Poland, Sweden, France and Austria. By the end of the 17th century, Brandenburg-Prussia was "the largest German principality after Austria". A couple of years later, and in a ceremony of enormous opulence, the Great Elector's successor, also named Frederick, was crowned "King in Prussia".

From here, Clark shows the Prussian state being strengthened and expanded through a series of annexations and wars. His interest in military technique is well exercised as he pursues his story through the 18th century, when yet another Frederick took over Silesia and Saxony, fought with the Swedes and grabbed large chunks of Poland. Then, in 1806, comes the "Napoleonic shock": a shattering defeat by the French at the battles of Jena and Auerstedt, which triggered extensive social and political reform. Clark attends to the revolutionary demands of 1848, here judged to have "constitutionalised Prussian politics without demilitarising the Prussian monarchy". He also gives due prominence to Bismarck, who became minister-president in 1862 and carried out further expansions, including the annexation of Alsace-Lorraine - a cause of lasting and fateful antagonism with France.

Clark skirmishes with received understanding as he goes. Twentieth-century historians were inclined to condemn Prussia as an authoritarian regime that had forged its own "special path" through history - one that side-stepped democracy and eventually delivered Germany into the hands of Kaiser Wilhelm II and then Hitler. If our mental picture of Prussia remains one of braided militarism, ruthlessly efficient bureaucracy and robot-like obedience to the state, this is because we still know Prussia in those terms. A "detestable" regime, so French voices cried after the first world war; "the source of the recurring pestilence," as Churchill declared a few years before defeated Prussia was finally wiped from the map in 1947.

Clark shows Prussia's course to be less an embodiment of evil, or an expression of "Teutonic" racial character, than the outcome of a defining historical experience. In his revised picture, the square-headed and patriarchal land-owning "Junkers" of well-known stereotype are moved aside to reveal the powerful and decisive women who actually shared power with them. The militarists, with their bristling moustaches and monocles, are forced to make space for the ranks of the anti-war movement, at times larger and more active than anywhere else in Europe. Karl Marx's claim that the forces of reaction were restored after the revolutions of 1848 is both granted and corrected with the insistence that there was never a question of rolling back the clock. Bismarck certainly took firm control over the democratic impulse, but he didn't wholly annul it, and his regime entailed social reform as well as "Iron and Blood".

There is much here for those concerned with the nation state and its development as a cultural and political construct. Clark gives us the high-born Fredericks and their courtiers but, aware of the call for "history from below", he seeks out the experience of peasants and industrial workers too. Attentive to questions of economics, military and industrial strategy and politics, he also engages the cultural dimensions of Prussian life and reviews their influence on the course of history. He considers the "invention of tradition" in Prussia, and the importance of memorials and ceremonies of remembrance in shaping patriotic identity. He covers the development of the press and other institutions of the public sphere that developed alongside Kant's ideas of enlightenment. He finds his material in novels, buildings and statues as well as state archives. Like most historians reaching out to the "general reader", he struggles to organise his material into a more or less coherent story, and yet he also knows that narrative has often been used to make the past reflect present wishes and prejudices.

It is only by contrary example that this book may remind us how miserable some hastily written products of the recent "history boom" have been. Clark is not one to swagger over the dead, secure in the knowledge that they cannot answer back. Instead, this is a well-informed and fair-minded historical investigation, written by a man who is plainly fascinated by the changing circumstances under which lives are lived and decisions made. One of the pleasures of this book is to watch Clark weighing the undeniable otherness of the past and resisting any tendency to convert it into a costume drama.

Iron Kingdom is written over such a wide canvas that even the most appreciative reader is likely to suffer moments of confusion. For me, the fog remained thick over Schleswig-Holstein. These northern duchies, which lie close to Denmark between the Baltic and the North Sea, have long since reverted to agrarian placidity within Germany, but they caused widespread alarm in the 19th century. Caught up in warfare between Denmark and Prussia, their future became connected with the ambitions of various rival powers, including Austria, Russia and Britain. All that you need to know about this flashpoint is presented here. However, I was grateful to Clark for admitting that most of the protagonists in this particular story seem to be named either Christopher or, indeed, Frederick.

· Patrick Wright's Tank is published by Penguin.