On July 7, 1953, a 25-year-old Ernesto Guevara, fresh out of medical school, set off from Buenos Aires for a trip abroad with a friend. Not long afterward, he remembered, “My departure, with so many people and a few tears thrown in; the strange looks of the people in second class at the sight of so many fine clothes, leather coats, etc. saying goodbye to a couple of odd-looking snobs loaded down with baggage.”

Neither he nor his well-dressed parents knew that they wouldn’t reunite for more than five years. When they did, it would be in Cuba, and young Ernesto would then be known to the world as “Che.”

Guevara kept diaries his entire adult life, and Back on the Road (Otra Vez) covers a crucial but up to now strangely obscure period. These writings, published for the first time, provide new links between the clean-cut, middle-class youngster who’d completed six years of medical study in three, and the long-haired firebrand who later emerged in Cuba.

The original of this sketchy, poorly annotated book, is a witness to that transformation. Tellingly, it doesn’t quite explain it.

From the outset, Guevara’s interests are overtly political. He longs to throw himself into the Third World’s struggle for liberation, but he has little political education and few connections. Soon enough, however, he’s visiting Bolivian mines, a trip which inspires this awkward, Neruda-inflected passage: “But the mine could not be heard throbbing. It lacked the energy of the workers who daily tear their load of materials from the earth, but who were in La Paz defending the Revolution. … ”

Often, this diary contains little more than jottings, and undated ones at that, of consulates he visited, jobs he found, friends he made and women he conquered; elsewhere, there are lengthy discussions of archaeological ruins. Even when not much is happening, the volume gives the impression of a man in a rush to make his date with history: Major personal developments are barely mentioned, such as his marriage to a Peruvian Communist, and the birth of their daughter.

Seemingly carried along by destiny, Guevara drifts into Guatemala in time to witness the CIA-sponsored overthrow of the left-leaning Arbenz regime. Guevara’s loud activism during the upheaval gets him deported to Mexico. It also attracts the notice of the CIA, which duly opens a file on him without his knowledge.

In Mexico, Guevara meets Fidel Castro, then in exile from Cuba. “He is a young, intelligent guy, very sure of himself and extraordinarily audacious. I think we hit it off well,” Guevara reports in a typically laconic entry.

Nowhere else in the book does he mention the man who would become a Lenin to his Trotsky.

This thin volume is fleshed out by the numerous letters Guevara wrote, mostly to his increasingly worried mother. These missives are much more revealing than the diaries: They show Guevara to be a self-consciously middle-class lad struggling to articulate his new revolutionary identity. “I am not Christ or a philanthropist, Mother; I’m the complete opposite of Christ,” he protested to her in 1956. “I fight for the things in which I believe, with the weapons in my reach, and I try to leave the other lying flat instead of letting myself be nailed to a cross or whatever…”

His other correspondent in the period is a woman named Tita Infante, a close friend and political soulmate from medical school. The book closes with a letter detailing tellingly juxtaposed events in November, 1956. “First, my little Indian girl is already nine months old, quite cute, very lively, and so on. The second and main thing is that, a while ago now, some Cuban revolutionaries asked me to help the movement with my medical ‘knowledge’ and I accepted. … Don’t write until you get my next letter, which will have more news or at least a settled address.”

He wasn’t kidding. The following month, Dr. Ernesto Guevara, now called Che, made his debut on the world stage when he, Fidel Castro and a few dozen comrades set sail for Cuba. EndBlock