Robert Lax became acquainted with Ernesto Cardenal through Thomas Merton, who served as Cardenal’s novice master when he was studying to be a monk at Gethsemani Monastery in Kentucky. Cardenal eventually left the Trappists and returned to his native country, where he served as Minister of Culture from 1979 to 1988, a tumultuous time in Nicaragua’s history. A celebrated poet, he did the Spanish translation for the multilingual version of Lax’s The Circus of the Sun, published by Pendo in 1981.
You can read more about Cardenal’s extraordinary life on his Poetry Foundation webpage.
And in his obituary from the The Guardian.
You’ll find many of Cardenal’s books in English and Spanish at Amazon, including a collection of his correspondence with Merton.