Born in Ibdes, province of Zaragoza, Aragon, Ezquerra started his career drawing westerns and war stories for Spanish publishers.

He drew "Rat Pack":[10] inspired by the film The Dirty Dozen, the strip, written by Gerry Finley-Day, featured a gang of criminals recruited to carry out suicide missions.

[8] In 1976 Battle editor Dave Hunt convinced him to commit himself to the title, offering him the laid-back anti-hero "Major Eazy", written by Alan Hebden.

[9] He returned to Battle, where he once again teamed up with Alan Hebden to create "El Mestizo", a black gun-for-hire who played both sides against the middle during the American Civil War.

In 1978 he and Wagner created "Strontium Dog", a science fictional western about a bounty hunter in a future where mutants are an oppressed minority forced into doing such dirty work, for Starlord,[12] a short-lived sister title to 2000 AD with higher production values.

[12] Ezquerra was almost the only artist to draw the character, until 1988, when writer Alan Grant decided to kill him off in a storyline called "The Final Solution".

[14] Other 2000 AD strips he drew included Fiends of the Eastern Front (1980), a vampire story set in World War II, written by Gerry Finley-Day, and adaptations of Harry Harrison's Stainless Steel Rat novels, with the title character once again resembling James Coburn.