Born in 1898, Seán Murray left school at eleven to help out on the small family farm near Cushendall in the Glens of Antrim. He resumed his education, after a fashion, in the cultural revivalist milieu and became an active republican in the aftermath of the 1916 Rising. Arrested for I.R.A. involvement during the War of Independence, he opposed the Treaty and remained a committed militant in his native area until circumstances obliged him to seek refuge in Scotland. Drawn to the emerging communist movement in ‘Red Clydeside’, where political connections of James Connolly's were relatively plentiful, he soon moved to London. Late in 1927 he was among the fledgling leaders selected to travel to Moscow to attend the Lenin School operated by the Communist International or Comintern (1919–43). This was the body charged with directing the efforts of recognised communist parties across the world. In Moscow, he faced more than two years of intensive Bolshevisation, a process which included education in Marxist economics, training in organisational and agitational methods, and conditioning in the observance of party discipline. He took the time to court and marry a Russian comrade who, however, was denied permission to accompany him to Ireland. That he did not contest the ruling was one indication that he had been successfully Bolshevised.

Seán Murray's time in Moscow coincided with the inauguration of pugnacious ‘third period’ Stalinist communism, to which he successfully adapted himself, and, alongside ‘Young Jim’ Larkin, he was given responsibility for re-establishing a communist movement in his native country. Young Jim's father had previously held the communist franchise for Ireland, but Jim Larkin senior was found to be insufficiently amenable to communist discipline. For most of the next thirty years – until his early death in 1961 – Seán Murray was at the core of the Irish communist movement, a movement which provoked odium out of all proportion to its small membership. If it did have some modest successes, the most notable of them was maintaining a continuous existence on the island.

Circumstances were less than auspicious as Murray embarked on his revolutionary career. Firstly, the ‘class against class’ orientation of third period communism, requiring a sharply critical approach to non-communist parties and groups, complicated relationships with disenchanted socialist republican elements of the I.R.A., regarded as the most likely source of recruits. Ill-considered interventions in its Irish sister party's affairs by the Communist Party of Great Britain added to the complexity of things. And opportunities were further limited by the concerted red scare launched by the Catholic church and the Irish state in 1931 in response to the socialist republican initiative, Saor Éire.

The socialist republican milieu was one to which Murray's background granted him easy access, and, third period policy notwithstanding, he was able to connect with Saor Éire. In 1934 he was a key figure in the abortive Republican Congress. These endeavours placed him in close contact with Peadar O'Donnell, novelist and sometime editor of An Phoblacht, with whom he would maintain a life-long friendship. Subsequently, as a Comintern proxy, Murray was centrally involved in the selection and vetting of the Irish volunteers who went to fight for the republican cause in the Spanish Civil War. Through various shifts and reorientations – including a complete reversal in relation to the Second World War – Murray remained a loyal advocate of Comintern policy for as long as there was a Comintern, and a defender of the actions of the Soviet Union. Falling out of favour, and out of communist employment, during the 1940s, he had returned to occupy a leadership position before the end of that decade.

In tackling Murray's life story, Byers sets himself the following objectives: detailing his subject's ‘considerable political activities and … delivering an intellectual history of Irish Communism and socialist republicanism between 1916 and 1962’ (p. 8). In these respects he succeeds, for this is a generally balanced and judicious work which, for this reviewer, engages carefully with writings critical of Irish communism, such as Mike Milotte, Communism in modern Ireland: the pursuit of the workers' republic since 1916 (Dublin, 1984) and Matt Treacy, The Communist Party of Ireland, 1921–2011: vol. 1, 1921–1969 (Dublin, 2012), as well as Emmet O'Connor, Reds and the green: Ireland, Russia and the communist internationals, 1919–43 (Dublin, 2004) and Adrian Grant, Irish socialist republicanism, 1909–36 (Dublin, 2012). The biographical lens indeed proves very useful here, for the fresh light it sheds on the political relationships on the Irish left which have been treated by the historians mentioned above. Moreover, in showing how Moscow's diktats were interpreted and implemented by one peripheral communist leader, Byers contributes to international debates about the relationships between the Stalinised Comintern and the communist parties subordinate to it.

Where the work falls short as a biography is in how little it communicates of the personality of the subject. In passing we learn that he was ‘self-effacing’, that he was affable, and that he may have gone ‘on the booze’ for extended periods, but such occasional details do not give the reader much sense of the rounded individual. It is a deficiency which is acknowledged in the introduction, where it is excused by reference to a skimpiness of source material. One feels however that more in this regard might have been squeezed from some of the sources cited, including the subject's creative writing, and the several of his acquaintances that were interviewed for the study. That quibble aside, the book may be recommended as a worthwhile contribution to the historiography of the Irish political left.