An exhibition about to open at the Museum of Liverpool pays homage to April Ashley, one of the first people ever to have gender reassignment surgery.

George Ashley – as she was born in Liverpool in 1935 – had the pioneering operation in Casablanca in 1960 after years of suffering. Feeling she was a woman in a man's body, she was beaten for being different as a child, then subjected to brutal psychiatric treatment as an adult.

What makes April Ashley an "icon", as the show calls her? Her courage in acting as a surgical and social "guinea pig" is just part of it. This exhibition is a collaboration with homotopia, Liverpool's international festival of queer culture, which this autumn also sees – among other events – an exhibition of David Hockney's early work at the wonderful Walker Art Gallery. She is being celebrated as a transsexual hero.

The fascination of April Ashley is surely that she raised all the issues around transgender life that are still debated today more than 50 years ago. In a way that was insouciantly subversive, she passed as a woman and was celebrated as an object of heterosexual male desire: she was a lingerie model for Vogue until a friend revealed her secret to the newspapers, for £5.

"Sexual intercourse began in 1963 (which was rather late for me)", as Philip Larkin wrote. April Ashley competed with the likes of Christine Keeler as a 60s sex symbol.

It is fashionable today to denigrate the 60s language of "sexual liberation" as naive and oppressive. Yet perhaps today's confusing and impenetrable confontations between some feminists and the transgender community could be healed by a look at the social history of the decade, and the life of April Ashley in particular.

She was born into a world where boys who acted like girls were beaten and reviled and scorned. She lived into – and helped create – a world where everyone has the right to the life they need to live. Isn't that, quite simply, liberating?