Joseph Mary Plunkett was born, November 1887, in Dublin. His father, Count George Plunkett, held a papal title and was at one time the Director of Dublin's Museum of Science and Art. Joseph was educated through the Catholic University School, Belvedere College and Stonyhurst College, and through his own broad reading.

He went to Thomas MacDonagh for lessons in Irish and they became friends and critics of one another's poetry, helping one another through publication. Aside from their common literary interests, they shared an interest in the Volunteer movement.

Joseph was for a short while editor of the literary publication, the Irish Review, which had on occasion published some of his poems. As editor, he encouraged not only not only literary contributions, but also discussions of current affairs, such as labour issues and anything of interest to the Volunteers.

He was also co-founder, with Edward Martyn and Thomas MacDonagh, of the Irish Theatre.

It was through MacDonagh that Joseph met Grace Gifford, whom he would later marry. Grace, daughter of a Dublin solicitor, was an artist and sister to MacDonagh's wife.

During the 1916 Rising, Joseph was stationed at the GPO, and he was one of the signers of the Proclomation of the Irish Republic. After the surrender to the English army, he was imprisoned in Richmond Barracks, and executed in the courtyard of Kilmainham jail, on the morning of May 4th, at the age of 28.

He and Grace had been married in the jail's chapel only a few hours earlier. His friend, Thomas MacDonagh had been executed the day before. Joseph's father, and his brother John, both also involved in the Rising, had their death sentences commuted to ten years' penal servitude. His wife, Grace, was later also imprisoned in Kilmainham.