The hat worn by Michael Mallin during the Rising, and pierced by a bullet on the second or third day of the fighting. The hat was returned to his wife, Agnes, by a British Army officer on the day following her husband’s execution.

Mallin, Michael Thomas (1874–1916), trade unionist and revolutionary, was born 1 December 1874 at Ward's Hill in the Liberties in Dublin. He was educated at Denmark Street national school, Dublin, and on 21 October 1889 joined the Royal Scots Fusiliers enlisting for twelve years, and was stationed at the Curragh. In 1896 his battalion went to India, where he served for six years. He took part in the Tirah campaign (1897–8) against insurgent tribes on the north-west frontier and contracted malaria, from which he suffered sporadically for the rest of his life. While serving in India, Mallin became disillusioned with military life and sympathetic to the Indian struggle for independence.

Upon his return to Ireland, he trained as a silk weaver. Active in socialist politics, he was a member of a unity committee formed to bring together opposing elements of the Irish socialist movement, which led to the founding of the Socialist Party of Ireland in August 1909.

When James Connolly took command of the Irish Citizen Army in October 1914 he appointed Mallin his chief-of-staff. Mallin was a popular and respected figure among his comrades. Although gentle and soft-spoken, he had a firm side to his character and insisted on strict discipline. Connolly had a high opinion of his abilities and left the business of organising and training the force largely to him.

In April 1916, on the Saturday prior to the Easter rising, Mallin was given the Irish Volunteer rank of commandant, and appears to have known of the plan weeks in advance.

He led the Citizen Army force that occupied St Stephen's Green on Monday 24 April, digging trenches in the park and erecting barricades on the surrounding roads; he appointed Constance Markievicz as his second-in-command. As dawn broke on Tuesday they came under fire from a machine gun on the roof of the Shelbourne hotel, suffering several casualties. Mallin himself had to drag a wounded man to safety and had a close shave when a bullet went through the brim of his hat.

Having received Connolly's confirmation of the order to lay down arms, Mallin surrendered along with his garrison of 109 men and 10 women on 30 April. Tried by court martial in Richmond barracks on 5 May, he denied holding a commission in the Citizen Army and claimed to be an ordinary soldier who had taken command of the St Stephen's Green garrison on Markievicz's orders. His anguish at leaving his pregnant wife and four young children was clearly evident in a letter written to Agnes on the eve of his execution. He was shot by firing squad in Kilmainham jail on 8 May 1916 and buried at Arbour Hill.

(Biographical information: Marie Coleman and James Quinn. 'Mallin, Michael Thomas'. Dictionary of Irish Biography)