As Michelle O’Neill walked down the marble staircase in Northern Ireland’s Parliament building on the outskirts of Belfast on Saturday, she appeared confident and calm. She smiled as applause erupted from supporters in the balcony. Only the seriousness of her gaze conveyed the gravity of the moment.
The political party she represents, Sinn Fein, was shaped by the decades-long, bloody struggle of Irish nationalists in the territory who dreamed of reuniting with the Republic of Ireland and undoing the 1921 partition that has kept Northern Ireland under British rule.
Now, for the first time, a Sinn Fein politician holds Northern Ireland’s top political office, a landmark moment for the party and for the broader region as a power-sharing government is restored. The first minister role had previously always been held by a unionist politician committed to remaining part of the United Kingdom.
“I am honored to stand here as first minister,” Ms. O’Neill said, first in Irish and then in English, after officially accepting the nomination to the post. “We mark a moment of equality and a moment of progress.”
The idea of a nationalist first minister in Northern Ireland, let alone one from Sinn Fein, a party with historic ties to the Irish Republican Army, was once unthinkable.
But the story of Sinn Fein’s transformation — from a fringe party that was once the I.R.A.’s political wing, to a political force that won the most seats in Northern Ireland’s 2022 elections — is also the story of a changing political landscape and the results of the 1998 Good Friday Agreement, which ended the decades-long sectarian conflict known as the Troubles.