The organisation claims that for every four Guernseymen who marched away, approximately one died.
Many more were wounded, and one family in Sark lost five sons in the hostilities. The population of the islands did not return to pre-war levels until the 1930s.
The Royal Guernsey Light Infantry Museum at Castle Cornet will open to the public this Remembrance Sunday between 10:00 and 13:00. A canon will fire at 11:00, and entrance is free.
Here, Express showcases some of the individuals, shared by Guernsey Museums, who ought to be in our thoughts this weekend.
Private Cyril Rabey was killed in action in 1917 at the age of just 19:
Private Charles Duncombe survived the war and returned to Guernsey, where he lived and worked until his death:
Private Theodore Zoel Agnès and Gunner Eugene G Agnès were both killed in action aged 35 and 21 respectively: