At a young age, he developed artistic tendencies: he played the piano, drew copiously and recited poetry.

Eielson switched schools several times until at the end of his secondary education he met the anthropologist and writer José María Arguedas who introduced him to the artistic and literary circles of Lima as well as to the knowledge of the ancient civilizations of Peru.

In the late 1950s, he abandoned avant-garde and resorts to using materials such as earth, sand and clay to sculpt in the canvas surface; at first he uses this technique to depict landscapes but gradually moves towards human figures represented through clothing of various kinds.

In 1963, he started his first quipu, reinventing this ancient Andean device with fabrics of brilliant colors, knotted and tied on canvas.

In the mid-1970s, he traveled to Peru where he devoted himself to the study of pre-Columbian art; during this period, the Instituto Nacional de Cultura (National Institute of Culture) published most of his poetry under the title Poesía escrita.