Actress Joan Plowright was made a Dame by the Prince of Wales at a ceremony at Buckingham Palace on Friday.
Dame Joan received the award from Prince Charles
She described herself as one of the "three musketeers" as she followed in the footsteps of her friends Dame Judi Dench and Dame Maggie Smith.
She added that she would later be hosting a party with her former female co-stars from Tea With Mussolini.
Dame Joan, the widow of Lord Laurence Oliver, said the award was "a kind of crowning in one's life achievement".
Of her late husband, she said: "He'd be delighted, absolutely delighted."
But she added she still found her new name difficult to come to terms with.
"It's a bit confusing. I've got so many names - Dame Olivier and Lady
Plowright. I just say call me Joan."
Dame Joan, 74, was named in the New Year's Honours list for her contribution to stage and screen, which has spanned more than 50 years.
She attended the Old Vic Theatre School at the age of 17 before joining the English Theatre Company at the Royal Court.
Among her credits are The Entertainer - in which she starred as the daughter of her real life future husband to be -, 101 Dalmatians and TV biopic Stalin in 1996.
Dame Joan's career has spanned more than half a century
She was nominated for a best supporting actress Oscar for Enchanted April in 1993, for which she won one of two Golden Globes.
"It's been worth it. It's always been a hard slog. People are usually not aware of this," she said.
"They're only aware of what seems to be the glamorous side, not the hard work
that goes into it."
During her investiture she chatted to Prince Charles about his visit to see her in the West End play Absolutely Perhaps, accompanied by Camilla Parker Bowles.
"They came back stage. I told him we were delighted they had done so," she