The internationally known Kenyan novelist Ngugi Wa Thiong’o has always been a political writer, and your appetite for overt politics will have a lot to do with whether or not you like Wizard of the Crow, his first novel since 1986. In a 1983 collection of critical writing, Barrel of a Pen, he analysed the cultural clash between People’s Artists and People’s Rulers. Wizard of the Crow is like a vivid, meandering, cartoon-like frieze dramatising this epic conflict.

Born in rural Kenya, Ngugi had a brother in the Mau Mau, and he himself became a courageous critic of colonialism and the post-colonial state. He was imprisoned under the dictatorship of Daniel arap Moi, after dropping the English of his first novels for his mother tongue, Gikuyu, thus gaining real and dangerous access to the people. Later, in American exile, he found a global reputation.

Wizard of the Crow, translated from Gikuyu, is his seventh novel and, he says, sets out to sum up Africa of the 20th century in the context of world history. How exactly can such a diverse continent be summed up? At great length, is the most obvious answer. This book is 767 pages long, and sometimes seems it. It is a satire on an invented African state, Aburiria. The American Global Bank acts as paymaster and puppet master to Aburiria’s monstrous Ruler, whose mysterious illness is the framework for the narrative. Why is the Ruler getting fatter and fatter? And why does he, like all his ministers and apparatchiks, smell so horribly of decay? The heroes of this book are two young lovers. Kamiti is a highly educated Aburirian man, a great respecter of Indian culture and an ecological thinker whose moral purity gives him an acute nose for the stench of corruption. He falls in love with Nyawira, who first appears as a secretary smelling of flowers but soon reveals her true colours as a scion of the secret Movement for the Voice of the People and a feminist activist, one of the women who set out to avenge themselves against Aburirian wife-beating and unfaithful husbands. Kamiti (surely a surrogate for the author, since his name is also the name of the prison where Ngugi was imprisoned in 1977) is more mystical, Nyawira more political, but together they embrace the identity of a two-bodied witch doctor, the eponymous Wizard of the Crow, whose supple, inventive thought at first challenges corrupt petty officials and later becomes the force that destabilises the Ruler himself.

Ngugi’s satirical targets are many: colonialism, corruption, misogyny, industrial pollution, snobbery within the church, racism, tribalism; and his tone broad. The form is inspired by oral epic, complete with magical transformations, astonishing escapes, and a loose, episodic structure. Most of the characters are physically grotesque: the Ruler slowly inflates during his illness, finally floating up off the ground in an attempt at divinity. He has two rival ministers, one, Machokali, with surgically enlarged eyes to help him spy, one, Sikiokuu, with similarly enhanced ears to help him listen.

My favourite strand in the novel is the daring satire on reverse racism. The most prevalent illness among the Aburirian leadership turns out to be white-ache, a longing to be white with all the power and respect that this would bring. But because this longing can never be spoken, those afflicted with it end up paralysed and at the mercy of the Wizard of the Crow, whose mirrors reveal what is in their hearts. The novel culminates in a giant set-piece festival where the Ruler’s inflation is revealed to be a pregnancy that belches out clouds of gas and finally Baby D (Baby Doc?), a newborn fictive democracy inspired by the cynical human rights requirements of the Global Bank.

Some of this burlesque is funny and lively, but there is a stiffness and didacticism about some of the good characters’ discussions that betrays a surplus of political conviction. Nevertheless, given the facts on the ground, the real-life Big Men now ruling in Africa and the global machinations of American finance, this satire linking the two still has an important point to make.

Available at the Sunday Times Books First price of £16.99 (inc p&p) on 0870 165 8585 and www.timesonline.co.uk/booksfirst

Times Recommends

• Why do Pynchon, Ballard and Wallace provoke such online loyalty?
• The Sunday Times 100 best holiday reads
• What will we be reading this summer: the booksellers predict