The Sword and the Cross by Fergus Fleming

The cheese-eating invasion monkeys

When it comes to the history of Western empires, the French can seem anomalous. Aiming to turn overseas subjects into quasi-Frenchmen, Gallic colonialism's distinctive ideals are still evident through the labelling of places such as French Guyana as "overseas departments"; colonies in Africa and Indo-China were extensions of the mother country, where the natives would be "pacified" and learn to eat baguettes.

The methods of this pacification form the subject of Fergus Fleming's excellent book on the French conquest of the Sahara at the turn of the 20th century. Though the story is brutal and depressing, the book is a chastening reminder of the nature of such endeavours.

The Sword and the Cross tells of two pivotal figures in the Saharan conquest: Henri Laperrine, whose campaigns in the Algerian sands crushed the Tuareg nomads, and Charles de Foucauld, an ascetic monk whose stoicism in desert oases attracted the Tuareg to France's "peaceful intentions".

Interwoven are the stories of various fantasists who sought the Sahara for France. Schemes included building a railway across the dunes, draining the Mediterranean into the Sahara, and creating ports on the Atlantic coast through dropping nuclear bombs. Meanwhile, many expeditionary leaders simply expressed their fantasies by butchering African peoples.

The violent and delusional pathologies of imperialism are powerfully exposed. Fleming's book is rich with insights on topics ranging from the colonisation process in Africa to the nature of faith. He underlines how religion and force combined to dominate the Sahara: while De Foucauld saw studying their language as a way to promote Christianity among the Tuareg, Laperrine saw it as a way to spread French rule. De Foucauld was the Christian flagpole on which Laperrine hoped to hang the tricolour.

Fleming's characterisation is unerring. There was nothing new to this "holy" alliance of faith and force, and Laperrine and De Foucauld were typical of their ilk. Laperrine was an efficient general, preoccupied with territorial expansion and his role in securing it. De Foucauld was an obsessive who took self-denial to extremes. Yet his Christian principles were challenged by the imperatives of empire, and he suffered inner conflicts. For both, the driving force of their lives led to violent ends.

France's Algerian colony ultimately collapsed in a bloody war of independence. Instead of attracting people to the "peacefulness" of Christianity and francophonie, French rule produced a resistance movement structured around Islamism, driven by a memory of the savage murders committed by French troops.

Naturally, the "barbarism" of the Algerian struggle wouldn't have surprised early standard-bearers of either cross or sword. De Foucauld talked of winning the hearts of the people, while Laperrine's motto was "to show force to avoid using it". Yet violently propagating Western ideals had the opposite of the desired effect. Algeria is today singled out as a centre of global terrorism.

As our leaders tunnel on in their own endeavours, Fleming's readers can only liken them to the French soldiers crossing the Sahara. These conscripts often slept covered by sand, as if blind to the world they sought to conquer, and to the legacy they would create.