Interesting book that covers the history of the CPI from foundation up to 1969. First volume of two. Based on some archival sources never previously used including from the Party's own archive. Some fascinating stuff about the Party's relationship to republicanism, including having at various times had members in the IRA and even Fianna Fáil!
The book proves conclusively that Coughlan - who had appeared to threaten Treacy over references to him in his book on the IRA - was a member of the party as was Roy Johnston at a time when they were leading advisors to IRA Chief of Staff Cathal Goulding. Johnston was in fact a member of the Irish Workers Party (as the southern CP was then called) while on the IRA Army Council!
The Communist Party of Ireland 1921 - 2011 by Matt Treacy (Paperback)