These are the battalions of the Welsh Regiment, sometimes known as the Welch Regiment, which have service personnel listed on Wars Last Goodbyes
They give a very illustrative picture of the local cost to communities when particular battalions went into action during war
Click on the battalion, and it might give you a better idea about the tragedies which went on at home as news of loved ones came home
If there are gaps, it will be because no goodbyes have yet been discovered for that battalion/unit/brigade/battery...
New Service Army