“Soldiers Died in the Great War” is a list of soldiers who lost their lives, compiled into a 1921 HMSO publication. The information was based on regimental records. It was originally published in a large number of regimental volumes, listing men by unit and surname. There was also a volume for commissioned men, “Officers Died in the Great War”. It is a generally reliable source but does (inevitably) contain some errors of fact and omissions.
Original and reprinted volumes are reasonably easy to find on the used book market and are held in many regimental museums.
The information has been digitised and is available from multiple paid sources.
Naval & Military Press
It was first released as a searchable database by Naval & Military Press in the form of a CDROM. It can still be purchased in this format. It is (at July 2020) list at £200, although it is often much reduced at sale times, so is best suited to those who will use this a lot, rather than the family historian who is looking for just or or two men.
The transcribed version of the paper volumes that forms the database has (again, inevitably) introduced some further errors although the publisher has eliminated some of them in second publication versions of the CDROM. Some still remain: for example, my great uncle James McSloy is hard to find as his surname is wrongly spelled.
The publisher now includes the database as part of their extensive offering at nmarchive.com: the Naval & Military Archive.
Other online sources
The same database appears to have been sold on to Ancestry and Findmypast (the same spelling error appears in both, which rather gives the game away).
TheGenealogist also has a database of “Soldiers Died” but the transcription error in James McSloy’s name does not appear – his name is spelled correctly – my conclusion being that this is from a different source rather than the Naval & Military Press version.
Forces War Records have combined the details from “Soldiers Died” with those available (free of charge) at the Commonwealth War Graves Commission website.
Ireland’s Memorial Records
This is a similar publication to “Soldiers Died the in the Great War” in that it draws upon exactly the same information. It is available as a DVD from Naval & Military Press but also via Ancestry. “Ireland’s memorial records” focused on men from Ireland and serving in Irish regiments.