All the walls of a city, which, by family tradition, seemed so mine, witnessed the martyrdom and the inhumane repression inflicted on our people. Cultural memories stressed its urgency. All the archaeological information I have absorbed, the advice of Leonardo da Vinci, the destruction brought about by Dada, the photographs of Brassaï, all contributed, unsurprisingly, to the fact that my first works of 1945 had something to do with street graffiti and a universe of repressed protest, clandestine yet full of life, as one could find on the walls of my country.

Tàpies is referring to the Franco-repression in Spain. - 'A Report on the Wall' 1970