Markievicz was released from prison on 27 August 1923 following her detention during the Irish Civil War for anti-Treaty activities.
On 27 August 1923, Constance Markievicz was released from prison following a period of detention connected to her anti-Treaty activities during the Irish Civil War (1922–1923). Having opposed the Anglo-Irish Treaty of 1921, which established the Irish Free State but retained partition and allegiance to the British Crown, Markievicz had aligned herself with the anti-Treaty republican forces led by figures such as Éamon de Valera.
Her imprisonment during this period reflected the deep and often violent split within the Irish nationalist movement following the Treaty's ratification, a conflict that pitted former comrades from the War of Independence against one another. As a prominent anti-Treaty figure, Markievicz's detention by the Free State government demonstrated the continuing personal risks she faced even after Irish independence had nominally been achieved.
Her release allowed her to resume active political life, and she went on to continue campaigning for republican and anti-Treaty causes throughout the 1920s. This period of imprisonment marked one of the final chapters in a lifetime marred by repeated incarcerations for her political convictions, underscoring her enduring commitment to a fully independent, republican Ireland even at great personal cost.