Of the five women in leading ministerial positions in the coalition, four are under 35.

Ms. Marin won the leadership vote by a small margin, and her leadership skills will be put to the test immediately as the country heads into a season of labor negotiations with the potential for strikes. Her predecessor, Mr. Rinne, was ultimately forced out of office after he made comments about a plan to cut wages for postal workers and his coalition partner, the Center Party, said it had lost confidence in him.

Despite his resignation, the coalitions parties will remain unaltered: Ms. Marins Social Democratic Party as Finlands biggest, the Center Party, the Greens, the Left Alliance and the Swedish Peoples Party of Finland.

The government under Ms. Marins leadership is expected to continue prioritizing job creation and ambitious climate goals, seeking to render Finland carbon neutral by 2035.

Johanna Lemola reported from Helsinki and Megan Specia from London.