Subcomandante Marcos, also known as Insurgente Marcos and Delegado Cero, is the anonymous spokesperson of the Zapatista Army of National Liberation, based in Chiapas, Mexico. The name Subcomandante Marcos is believed to be an acronym that makes reference to some of the first locations where the army started their fight. Subcomandante Marcos has made clear in different occasions that he is not the leader of the Zapatistas, but rather a supporter. The army, consisting mainly of indigenous Mayans, also counts with the support of white rural workers and sympathizers who understand the plight of the locals.

Subcomandante Marcos has never revealed his true identity, but the Mexican government believes his real name is Rafael Sebastián Guillén Vicente. Guillén was an active member of the Institutional Revolutionary Party while he was teaching Philosophy at Metropolitan Autonomous University (UAM) in Mexico City, which would go along with Subcomandante Marcos's speech that the "Zapatista movement is more about ideas than bullets."

The Zapatistas believe in non-violent protest, and make active use of peace marches and the Internet to share their message. They oppose globalization and fight for the autonomy of the native population of Mexico. Subcomandante Marcos has also widely campaigned against the World Trade Organization and the economic sanctions imposed by the United States on worldwide markets.

Since 1996, Subcomandante Marcos has written 21 books, some of which have gone on to be printed in numerous editions and translated into several languages. La Historia de los Colores / The Story of Colors, a bilingual edition of one of his most famous books, is actually a retelling of an old Mayan children's fable that speaks of tolerance and solidarity. Subcomandante Marcos is also an avid correspondent, having written more than 250 stories and essays directed to newspapers and magazines, or used as press releases.

In 2005, Subcomandante Marcos announced a two-part plan called "The Other Campaign." While the creation of the plan coincided with Mexico's presidential election the following year, the aim of the Zapatistas is not to back any particular candidates. Instead, they request a new national constitution that emphasizes equality and guarantees that public resources will not be sold to private powers. Since the beginning of "The Other Campaign," Subcomandante Marcos has been traveling Mexico in search of supporters while addressing the issue of poverty and oppression.