America, wrote Ishmael Reed in his 1972 novel Mumbo Jumbo, is “mercurial, restless, violent ... the travelling salesman who can sell the world a Brooklyn Bridge every day, can put anything over on you”.

Forty-five years later, Reed has performed a magic trick reminiscent of something found in that book, a dazzling novel about Voodoo, jazz and white supremacy: his personification of the US has taken a step beyond rhetoric and become flesh, in the mercurial, violent and restless salesman who is now America’s president.

Mumbo Jumbo, which has just been reissued as a Penguin Modern Classic, reeks of some kind of immortal pertinence. Reed has a certain immortality himself, as the author of novels, poetry, plays and music for more than 50 years. His work is embedded in every level of black culture in America. He has written about Muhammad Ali and Barack Obama; in turn, Tupac Shakur once rapped about him. (“My man Ishmael Reed” makes an appearance in Still I Rise.)

His 10 novels are, for the most part, subtle satires on race, worked into settings such as the OJ Simpson trials, a US civil war in which photocopiers exist and a wild west where cowboys wield laser guns. But Mumbo Jumbo is the most dazzling of them all. Set ostensibly in the 1920s, Reed’s novel follows conspiracy theories ranging backwards and forwards through time. A “plague” called Jes Grew has spread from New Orleans and caused half the country to dance recklessly, enjoy jazz and have a new appreciation for African American culture. Religious orders like the Knights Templar and the hi-tech Wallflower Order (responsible in Reed’s novel for the Depression and the US occupation of Haiti) seek to destroy an ancient Egyptian text that the Jes Grew may “want”.

Like jazz, the novel feels improvisatory and ambitious.

But Jes Grew is “an anti-plague”, the spirit of innovation and freedom of self-expression itself: “Jazz. Blues. The new thang … Your style.” Reed took a snatch of the preface to 1922’s The Book of American Negro Poetry, in which James Weldon Johnson says “the earliest Ragtime songs, like Topsy, ‘jes’ grew’” – they just happened – and turned it into a clever literary device that exposes people’s prejudice.

While some believe the media invented Jes Grew to sell papers, Harlem Voodoo priest Papa LaBas is drawn into the search for its ancient text. Unbeknown to him, a Muslim scholar has already found it, translated it and had it rejected by a publishing house. The slip is found next to his dead body: “The ‘Negro Awakening’ fad seems to have reached its peak and once more people are returning to serious writing … A Negro editor here said it lacked ‘soul’ and wasn’t ‘Nation’ enough.”

Made up of newspaper cuttings and party invites, handwritten notes and footnotes, contemporaneous and contemporary photographs, Mumbo Jumbo gives one a sense of Reed just using everything that captures his own imagination. This is exhilarating because, like jazz, the novel feels improvisatory and ambitious. Reed embraces ridiculousness, while lending the ridiculous weight. It is a funny book about conspiracy theories that nonetheless feels serious and true, encompassing potted histories of Voodun loas and the Crusades, essays on Christ’s laughter and the cotton trade (“Was it some unusual thrill at seeing the black hands come in contact with the white crop?”), and a postmodern alternative creation myth involving Osiris, Incas, Homer and Moses.

The weight of ideas, along with the time-hopping and slapstick, makes Reed’s book read like something by contemporary novelist Ned Beauman. Or rather, Beauman’s books feel at home in Reed’s lineage: Beauman takes his cue from Pynchon, and Pynchon admires Reed, even name-checking him in Gravity’s Rainbow: “Well, and keep in mind where those Masonic Mysteries came from in the first place. (Check out Ishmael Reed. He knows more about it than you’ll ever find here.)”

It is tempting to say that Mumbo Jumbo is “prophetic”, shining a spotlight on the US’s modern racial tensions: the vilification of the #blacklivesmatter movement, the sudden political prominence of white supremacists, Twitter outrage when Netflix commissions a show called Dear White People. But this would be patronising. The truth is that, since Reed saw his novel published in 1972, the world has changed very little. The only upshot is that we can read his work now with a similar urgency to what its first readers might have felt.

Yet there is a rightness to Mumbo Jumbo – already considered one of the best novels in the western canon by revered critic Harold Bloom – being canonised as a Penguin Classic a year after Paul Beatty’s Man Booker win for The Sellout, another philosophical and ingenious American race satire. As Papa LaBas says, Jes Grew is always there, always observable. But it flares up when “something is going on”. No one can deny, in the US today, that something is going on, and needs to be addressed.