In 1923 8 volumes of 'Ireland's Memorial Records' were published, the purpose of which were to provide a remembrance of those Irish men and women who died in the Great War. It was a wonderful undertaking and a very polished end product. For almost 100 years it was accepted as the most comprehensive listing of our Irish heroes of the Great War, but nonetheless it had an Achilles heel in that there were many omissions: specifically, it did not record many R.A.F./R.F.C., Mercantile Marine, South African Army, Canadian Army, or U.S. Army casualties. Its greatest failing was that it assumed every man in an Irish regiment of the British Army was an Irishman. '26 County Casualties of the Great War' is the 21st century undertaking of this task, covering in greater detail the casualties of those belonging to the 26 counties of the now Republic of Ireland. We will remember them.