Almost a century ago, Éamon de Valera quit as president of Sinn Féin after he lost a vote over whether his party should take their seats in the Free State Dáil.

https://www.independent.ie/irish-news/fianna-fail-politicians-arrived-in-leinster-house-with-guns-a-look-back-at-100-years-of-the-party-founded-by-eamon-de-valera/a1671529659.html