1 February 1878|
Cloughjordan, County Tipperary, Ireland
|Died||3 May 1916
Kilmainham Gaol, Dublin, Ireland
|Years of service||1913–1916|
|Commands held||2nd Battalion|
Early life 
MacDonagh was born in Cloughjordan, County Tipperary. He grew up in a household filled with music, poetry and learning and was instilled with a love of both English and Irish culture from a young age.
Both his parents were teachers; who strongly emphasized education. MacDonagh attended Rockwell College. While there MagDonagh aspired to become a priest or brother and spent several years studying for this the vocation, however, after a few years he realized that it wasn't the life for him, and left.
He had abandoned a vocation for the priesthood, which came with the stigma of being "a spoiled priest". Very soon after, he published his first book of poems, Through the Ivory Gate, in 1902. He moved to Dublin where he joined the Gaelic League, soon establishing strong friendships with such men as Eoin MacNeill and Patrick Pearse.
Teaching career 
His friendship with Pearse and his love of Irish led him to join the staff of Pearse's bilingual St. Enda's School upon its establishment in 1908, taking the role of teacher and Assistant Headmaster. He also founded the teachers' trade union ASTI (Association of Secondary Teachers in Ireland). Though MacDonagh was essential to the school's early success, he soon moved on to take the position of lecturer in English at the National University. MacDonagh remained devoted to the Irish language, and in 1910 he became tutor to a younger member of the Gaelic League, Joseph Plunkett. The two were both poets with an interest in the Irish Theatre, and formed a lifelong friendship.
In January 1912 he married Muriel Gifford, a Protestant who converted to Catholicism; their son, Donagh, was born that November, and their daughter, Barbara, in March 1915. Muriel's sister, Grace Gifford, was to marry Joseph Mary Plunkett hours before his execution in 1916.
In 1913 both MacDonagh and Plunkett attended the inaugural meeting of the Irish Volunteers and were placed on its Provisional Committee. He was later appointed commandant of Dublin's 2nd battalion, and eventually made commandant of the entire Dublin Brigade. Though originally more of a constitutionalist, through his dealings with men such as Pearse, Plunkett, and Sean MacDermott, MacDonagh developed stronger republican beliefs, joining the Irish Republican Brotherhood (IRB), probably during the summer of 1915. Around this time Tom Clarke asked him to plan the grandiose funeral of Jeremiah O'Donovan Rossa, which was a resounding propaganda success, largely due to the graveside oration delivered by Pearse.
Easter Rising 
Though credited as one of the Easter Rising's seven leaders, MacDonagh was a late addition to that group. He didn't join the secret Military Council that planned the rising until April 1916, weeks before the rising took place. The reason for his admittance at such a late date is uncertain. Still a relative newcomer to the IRB, men such as Clarke may have been hesitant to elevate him to such a high position too soon, which raises the question as to why he should be admitted at all. His close ties to Pearse and Plunkett may have been the cause, as well as his position as commandant of the Dublin Brigade (though his position as such would later be superseded by James Connolly as commandant-general of the Dublin division). Nevertheless, MacDonagh was a signatory of the Proclamation of the Republic.
During the rising, MacDonagh's battalion was stationed at the massive complex of Jacob's Biscuit Factory. On the way to this destination the battalion encountered the veteran Fenian, John MacBride, who on the spot joined the battalion as second-in-command, and in fact took over part of the command throughout Easter Week, although he had had no prior knowledge and was in the area by accident. MacDonagh's original second in command was Michael O'Hanrahan.
As it was, despite MacDonagh's rank and the fact that he commanded one of the strongest battalions, they saw little fighting, as the British Army avoided the factory as they established positions in central Dublin. MacDonagh received the order to surrender on April 30, though his entire battalion was fully prepared to continue the engagement. Following the surrender, MacDonagh was court martialled, and executed by firing squad on 3 May 1916, aged thirty-eight.
His widow died of heart failure while swimming in Skerries, County Dublin on 9 July 1917; his son Donagh MacDonagh became a prominent poet, playwright, songwriter and judge. He died in 1968. In addition, his extended family were spread across Britain and Ireland and as part of the worldwide Irish diaspora.
Reputation and commemoration 
MacDonagh was generally credited with being one of the most gregarious and personable of the rising's leaders. Geraldine Plunkett Dillon, a sister of Joseph Plunkett gives a contemporary description of him in her book All in the Blood: "As soon as Tomás came into our house everyone was a friend of his. He had a pleasant, intelligent face and was always smiling, and you had the impression that he was always thinking about what you were saying." In Mary Colum's Life and the Dream, she writes of hearing about the Rising from America, where she was living with her husband, Pádraic Colum, remembering Tomás MacDonagh saying to her: "This country will be one entire slum unless we get into action, in spite of our literary movements and Gaelic Leagues it is going down and down. There is no life or heart left in the country."
Thomas MacDonagh Tower in Ballymun, Dublin, which was built in the 1960s and demolished in June 2005, was named after him, as was the train station (MacDonagh Station) and shopping centre (MacDonagh Junction) in Kilkenny (as MacDonagh had taught in St Kieran's College, Kilkenny City during the early years of his career).
His works include:
- April and May
- When the Dawn is Come
- Songs of Myself
- Lyrical Poems
- Thomas Campion and the Art of English Poetry
- Literature in Ireland (published posthumously)
- "MacDonagh, Thomas". The Catholic encyclopedia: an international work of reference on the constitution, doctrine, discipline, and history of the Catholic church 17. The Catholic Encyclopedia Inc. 1922. p. 477. Retrieved 9 Nov 2010.
- Roche, Anthony (2005). The UCD aesthetic: celebrating 150 years of UCD writers. Dublin: New Island. p. 31. ISBN 978-1-904301-82-0.
- Walsh, Brendan (2007). The pedagogy of protest: the educational thought and work of Patrick H. Pearse. Peter Lang. p. 226. ISBN 978-3-03910-941-8.
- Norstedt, Johann (Fall, 1984). "The gift of reputation: Yeats and MacDonagh". Éire-Ireland: a journal of Irish studies (Irish American Cultural Institute) 19 (3): 136. ISSN 0013-2683. Retrieved 13 Nov 2010.
- McBrien, Richard P. (25 Apr 1997). "The lesson of Heaven's Gate". National Catholic Reporter (Kansas City, MO: The National Catholic Reporter Publishing Co). Retrieved 16 Nov 2010.
- "Thomas MacDonagh". Ricorso. Retrieved 17 Nov 2010.
- A clip of three of Thomas MacDonagh's students' recollections
- Kilmer, Joyce (1916-05-07). "Poets Marched in the Van of Irish Revolt; Pearse and MacDOnagh, Executed Last Week, Well Known for Their Verse;;-Other Writers Prominent in Sinn Fein Ranks". New York Times. Retrieved 2008-08-08. New York Times, May 7, 1916 by Joyce Kilmer. This is made available online for free in the pre-1922 NYT archives.