For others already active in the abortion rights campaign, Dr. Halappanavar’s death marked a visible turning point. Thousands rallied outside the Irish Parliament in 2012 after news of her death, and marches and vigils followed. As the years went on, her name became a rallying cry.

Mark O’Halloran, an actor and a screenwriter, was at those initial protests in 2012.

“The call for change was already there, but I don’t think there was much momentum, I don’t think there was much political will,” Mr. O’Halloran said. “The people of Ireland were shocked by it, and it changed a lot of people’s minds.”

There had been other prominent cases after the Eighth Amendment was introduced, but never one that galvanized so many people across so many demographics, he said. In 1992, a 14-year-old rape victim was prevented from traveling to Britain for an abortion, in an episode that came to be known as the “X case.” Her name was never released to protect her identity.

Dr. Halappanavar’s husband and friends gave accounts of her life and of her final days in a hospital. The public also saw videos of her full off life. Mr. O’Halloran said he believed that a deeply ingrained sense of responsibility that Irish people feel for visitors and newcomers weighed heavily on the conscience of the nation.

“The fact that all of those old, ideological hangups contributed to her death, and the fact that she and her husband were told, ‘This is a Catholic country, we can’t help you’ — that really brought terrible shame on us,” Mr. O’Halloran said.

Dr. Halappanavar’s parents gave permission for her image to be used by the campaign to repeal the amendment.

“I hope that the people in Ireland will remember the fate of our daughter Savita on the day of the referendum and vote ‘yes’ so that what happened to us won’t happen to other families,” her father, Andanappa Yalagi, said in a video clip posted by the Together for Yes campaign ahead of the vote.