Born and raised in Puerto Rico in the 1930s.
Worked for American newspapers as an illustrator and a translator of comic strips. When he trtanslated a novel, Lydia Bailey, into Spanish, he also designed a cover for its Spanish edition.

Around 1945, Palacios shared a studio with Edgar Cirlin, Ava Morgan and Riki Levinson. Cirlin's agent, Nettie King, obtained a number of freelance assignments for him, and Gobin Stair, art director at Bantam Books and friend of the group, had him do covers for Bantam; the first was for number 10, South Moon Under. For some Bantams, Palacios did both covers and endpapers, often putting a diagram or map on the latter.

Later he concentrated exclusively on cartography; his maps for Dwight Eisenhower's Crusade in Europe were, in 1949, his breakthrough into that field. He has also done hardcover jackets for Doubleday and other firms, using a noteworthy combination of figurative design and cartography.

(from The Book of Paperbacks by Piet Schreuders, Virgin Press, 1981)