Helen Wagner: Actress who appeared in the US soap ‘As the World Turns’ for more than half a century

When Helen Wagner took the role of the matriarch Nancy Hughes in the first episode of the American daytime serial As the World Turns in 1956, she had no idea that she would still be there 54 years later.

Nancy remains the longest-running television character played by one actor and, as an enduring soap star, Wagner is beaten only by Lesley Saweard and the late Norman Painting of the radio serial The Archers.

"Good morning, dear," were the first words that viewers heard in As the World Turns as Nancy sat up in her twin bed, talking to her lawyer husband, Chris (Don MacLaughlin). Over more than half a century, the straitlaced, mild-mannered wife and mother Nancy saw a lot of change in the turning world, including the death of her husband, a second marriage – to a detective, Dan McClosky (Dan Frazer) – his battle with Alzheimer's disease and his eventual death. However, the actress described Nancy as "a tent-pole character", explaining that, "Nothing ever happens to Nancy. She's the one the others come and talk to."

Although she clocked up records for her long run, Wagner was twice written out of the soap, only to return when loyal viewers protested. Her appearances became less frequent over the years and she was last seen in the fictional town of Oakdale, outside Chicago, in April this year. She almost completed the soap's full run – it is being axed in September after 54 years.

Born in Lubbock, Texas in 1918, Wagner studied music and drama at Monmouth College, Illinois, graduating in 1938. A talented mezzo-soprano, she performed with the St. Louis Municipal Opera Company before appearing on the Broadway stage in the musicals Sunny River (1941-42) and Oklahoma! (1943-48), and Shakespeare's The Winter's Tale (1946). Wagner also played Blanche in a tour of A Streetcar Named Desire, alongside Lee Marvin.

One of her earliest small-screen roles was as Trudy Bauer – a child in a lower-middle-class, German immigrant family – in the original, 1952 cast of the world's longest-running television soap opera, Guiding Light, which had begun on radio in 1937. However, she left after two months. (The television cast also acted in the radio version until that was dropped in 1956. The screen version finally ended last year.)

Wagner then acted another Trudy in the soap Valiant Lady (1953-54), and Marge Franklin, daughter of the small-town general-store owner played by the comedy actor Charles Ruggles, in the sitcom The World of Mr Sweeney (1954).

When Guiding Light's creator, Irna Phillips, launched As the World Turns in 1956, she cast the actress as Nancy Hughes. Phillips sacked her after six months, dissatisfied with the way that she poured coffee – an important task for a character who provided a sympathetic ear and a shoulder on which to cry – but she was soon reinstated. Wagner's departure was also brief when, in the 1980s, she was dropped by a new producer who wanted the programme to appeal to a younger audience.

On 22 November 1963, Nancy was discussing plans for Thanksgiving when the live broadcast was interrupted by Walter Cronkite's first newsflash announcing that President Kennedy had been shot in Dallas. Wagner later said that she continued with the scene, not knowing of the shocking news at the time.

She lamented that her character was featured less prominently over the years, saying in 1988: "I don't like the making of Nancy into only an extra figure at parties. She is too dynamic a person to be made into a ghost."

The actress was presented with the National Academy of Television Arts and Sciences' Lifetime Achievement Award in 2004. Wagner's husband, Robert Willey, an actor and theatre producer who became her manager after their 1954 marriage, died last year.

Helen Losee Wagner, actress: born Lubbock, Texas 3 September 1918; married 1954 Robert Willey (died 2009); died Mount Kisco, New York 1 May 2010.