Xavier was born in Vera de Bidasoa on 16 January 1915, son of the writer and journalist Javier Bueno, then correspondent in Berlin for the Madrid newspaper ABC.
He spent part of his childhood in Spain where he attended the Academy of San Fernando in Madrid with Velasquez Diaz and in 1925 he moved with his family to Geneva where he enrolled at the Academy of Fine Arts.
In 1937 he moved to Paris and presented his works, characterized by a strong imprint of “Spanish” realism, at the “Salon des Tuileries”, at the “Salon d’Automne”, at the “Salon des Indépendants” and at the “Salon d’art Mural”; he also exhibits at the Spanish Pavilion of the New York Universal Exhibition. In 1938 Xavier was joined in Paris by his brother Antonio, three years younger and also definitively devoted to painting. From this moment, and for a period of approximately ten years, a total partnership was established between the two.
In January 1940 he moved to Italy, where, in 1947 he joined together with his brother Antonio, Pietro Annigoni and Gregorio Sciltian in the group of “Modern Painters of Reality”.
The experience of the Spanish civil war first and then the Italian one, increasingly directing the artist towards a realism linked to motifs of strong social content.
At the end of the 1940s, coinciding with the crisis of the group, the relationships between Xavier and his brother Antonio begin to change, after years of shared path. The causes are to be found in the progressive diversification of their respective artistic personalities. However, it was a more stylistic-conceptual disagreement than a human-personal one.
An important stage in Xavier’s life was the trip to Brazil in 1954: the artist returned from this experience full of enthusiasm and with a series of inks whose main protagonists were children, teenagers and labourers. From this moment the theme of childhood becomes more and more recurrent, the characters will be depicted immobile, in a sort of unreal fog, even devoid of depth, of perspective rigor, from which they emerge as if evoked.
The memory of Xavier traced by the poet Salvatore Quasimodo is emblematic: «Bueno’s still lifes raised in bottomless space deserve special attention, in which thicknesses are created by the rhythm of objects, removed from a metaphysical absence.»
Between 1959 and 1964 Xavier created the “Children” cycle, suffering and melancholic images, symbolic works of a dejected and oppressed humanity, which the artist presented at the “España libre” exhibition.
Since then his research has explored this direction in depth, proposing his characteristic images of the tender faces and immature bodies of adolescents, until his death in Fiesole in 1979.