Voted the sexiest man in the country by Mexican women and showered with mail from female fans at his jungle hide-out, the pipe-smoking rebel in the black balaclava is believed to be anything but homosexual.
Behind the balaclava, only his pale eyes had been seen by the public until the government last week "unmasked" the mystery man as a young-looking leftist called Rafael Sebastian Guillen, a child of '68, doctor of philosophy and son of a well-off furniture dealer from the northern city of Tampico.
Beleaguered Mexican President Ernesto Zedillo apparently believed that revealing Marcos's true identity would explode the myth and help the government regain the upper hand against the rebels in the southern state of Chiapas. Mr Zedillo may have miscalculated.
With the slogan "Todos somos Marcos" ("We are all Marcos"), a nationwide movement has built up in sympathy with the guerrilla leader and his cause of improving the lot of Mexico's downtrodden indigenous population. The gay rights protester was typical of how the masked rebel has come to be seen as a mixture of the Lone Ranger, Robin Hood and Mexican revolutionary hero Emiliano Zapata, after whom he named his movement.
Young men and women don Marcos-style balaclavas at anti-government demonstrations, Marcos dolls made by Indian peasant women sell like hot cakes and Marcos T-shirts are the fashion. Even a protest march by old people in Mexico City last week which began with calls for higher pensions ended with white- haired men and grandmothers spontaneously chanting "Long Live Marcos".
More than a week after Mr Zedillo launched a military offensive against him and ordered his arrest on charges of sedition, mutiny, treason and terrorism, Marcos is apparently alive and well and living in the Lacandon jungle with 10,000 men at arms and 20,000 civilian sympathisers. In a statement smuggled through army lines, he mocked the President and said he will continue to resist until he is killed or Mr Zedillo falls and the system that has kept one party in power for 65 years collapses.
As in mid-December last year, when the Zapatistas' surprise takeover of 38 towns helped spark the devaluation of the peso and a financial crisis, the Mexican stock market appeared to take the guerrilla chief seriously. It slumped by 6 per cent on Wednesday as a desperate Mr Zedillo switched signals, ordering a halt to the military offensive and saying he would talk to the guerrilla leaders he had branded as criminals and traitors only a few days earlier.
Marcos was first seen in the small hours of New Year's Day 1994, when he and a couple of hundred Indian peasant guerrillas decided to first- foot the town hall in the colonial Chiapas town of San Cristobal de las Casas. Instead of whisky and lumps of coal, they carried rifles and machetes and took the building after a brief gun battle.
Sporting the balaclava, crossed bandoliers of cartridges, a black overcoat and an Uzi submachine gun, he chatted in English, French and Italian to gaping tourists who had been celebrating the New Year when the guerrillas marched in.
He later said he had not expected to get away with the assault, only a few miles from a major army garrison: ``That night, we thought the world was going to cave in on us. Now I'm living on borrowed time.''
His Zapatista National Liberation Army (EZLN) later took control of a large area on the edge of the Lacandon jungle, a zone which the army retook last week as the guerrillas retreated. The EZLN had turned the zone into an autonomous territory, imposing its own laws, including a ban on alcohol, which has become a serious problem among Indian peasants in Chiapas, encouraged by unscrupulous caciques, traders who have a monopoly on cheap locally made spirits.
He may have lost his territory and his anonymity, but the Marcos legend continues. He took to wearing a military fatigue cap atop the balaclava and appeared for jungle press conferences on horseback like a modern Zapata.
His ``unmasking'' last week merely confirmed what his writings and press releases had suggested: that he is better-educated than most of the cabinet and has something Mr Zedillo has yet to demonstrate - a sense of humour.
Nicknaming himself ``El Sub'' (short for subcomandante), he has described himself as ``a genial myth''. He studied at the Sorbonne and was influenced by the French student revolt of 1968 and the massacre of hundreds of students that year in Mexico City by the army after protests against spending on the Olympic Games. The killings marked a watershed in the movement to establish democracy in a country ruled by the Institutional Revolutionary Party (PRI) since 1929.
Marcos has sent letters, poems, plays and film screenplays to Mexican newspapers and has engaged in correspondence with readers. Replying to a letter from a schoolboy, the rebel leader wrote: ``The revolutionary loves life without fearing death and seeks a life of dignity for everyone. If he has to pay for that with death, he will do it without drama or fuss.''
He joked with reporters who reached him about whether he should seek sponsorship from a soft drinks company or perhaps auction off his balaclava at Sotheby's. ``How much do you think it would fetch?'' he asked.
His last published statement, written after the President sent the army against him, was his usual mixture of pathos and humour. ``Zedillo knows how to deal with figures, macroeconomic plans, lying media and submissive opposition politicians, but not with human beings,'' he wrote. ``Let's see if he learns, before the whole thing falls apart."