Together with Esteban Vicente (1903-2001), the other Spanish member of the American abstract expressionist school, Guerrero is one of Spain’s most international artists.

After training in Madrid and sojourns in Paris and Rome, where he met his future wife Roxanne Pollock, in 1949 Guerrero moved to New York, where was just coming into its own. He soon joined the movement, and was particularly active in the abstract style known as

 colour field painting 

a style of abstract painting associated with Abstract Expressionism in which artists work with large fields of colour, endowing their paintings with a mystical aura. Practitioners of colour field painting include Mark Rothko, Barnett Newman and Clyfford Still.

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In the 1960s he returned to Spain, where he found a favourable climate to continue developing his vibrant palette. His creative process focused on experimentation with painting itself, through which he reflects his personal experience in the form of colour: “Colour spreads, it does not stop,” as he said in 1988.

This work reflects Guerrero’s vitality and love for paint, a liquid colour applied with free-flowing brushwork. He worked in a very bright chromatic range in an unmistakably Spanish tone, with a luminosity characteristic of the hot climate of his native Andalusia.

For Guerrero, colour has a subjective association that he frequently deciphered through psychoanalysis —which he underwent for four years— and that remits to his childhood, to nature, to sensuality... always accompanied and accentuated through black, the central focus of his series Comienzo, or beginning in English. In his own words, black is a reflection he perceives “in people, in the landscape, in loneliness,” very different to the black of the El Paso group, because here he is talking about his youth cloaked in mourning and the tragic death of his father and his siblings. Black contrasts with the large areas of yellows, reds, pinks and blues, the colours most frequent in his palette and also present in this series.