In the 1950s, two Basque sculptors loomed large on the international scene. Eduardo Chillida (b. 1924; d. 2002) received the Diploma of Honor at the Milan Triennial in 1954, and in 1958 he won the Grand Prize for Sculpture at the Venice Biennale; and Jorge Oteiza (b. 1908; d. 2003) was granted the Diploma of Honor at the Milan Triennial in 1951 and the International Sculpture Prize at the São Paulo Biennial in 1957. Though the two artists had very different beginnings, their paths converged in several major artistic projects like the Aránzazu Basilica and the founding of the GAUR group, part of the Basque School movement.
Oteiza’s oeuvre defies easy classification and transcends the sculptural object, for each piece is merely the end result of a long process of experimentation with mass and space, developed in groups or series of pieces that share a common concept. A case in point is his “conclusive works,” which include the Empty Boxes (1958) and Metaphysical Boxes (1958–59) that took his investigations to the next level. These creations signal the evolution toward a purely receptive space, the void or emptiness, which Oteiza associated with the microlithic cromlechs of the Basque Country.