With fewer than 100 days to go until November 11, the charities are urging people to mark the centenary of the end of the Great War.
Tens of thousands of Scots died in the catastrophic conflict, while some estimates put British and Commonwealth dead at close to one million, and total losses for all protagonists at around 40 million dead - of whom around half were civilians.
Yet despite the scale of the worldwide disaster another world war erupted just 21 years later, spreading mass murder across the globe.
The Second World War was fuelled by political and economic chaos, and by appeasement policies which permitted the growth of fascism in Spain, Japan, Italy and Germany.
The origin of internecine conflicts which persist today are regularly attributed to the terms the victors arranged for themselves in 1918 - particularly in the Middle East.
However the campaign, launched yesterday in Dundee, invites people to explore First World War heritage where they live and “find reasons for giving thanks”.
Kevin Gray MM, chief executive of Legion Scotland, said: “Very few, if any, local communities were left untouched as a result of the First World War.
“Their generation served at home or on the front line - they sacrificed, and their combined efforts changed our world.
“We owe them two simple words that mean so much and show our gratitude”.
He added: “My great uncle was from a small community in Islay.
“He served with the 1st Battalion Cameron Highlanders. He was 23 years old when he was killed in action in France on September 28, 1915. He is laid to rest in the Ninth Avenue Cemetery, in Haisnes. ‘Thank You’ is the very least we should say.”
Mark Bibbey, chief executive of Poppyscotland, said: “We all have a connection to the First World War, and, for me, it is through both of my grandfathers.
“My paternal grandfather served in the Royal Welch Fusiliers on the Western Front from 1916 to 1918, while my maternal grandfather was in the Royal Army Service Corps attached to the London Yeomanry and served in Egypt, Gallipoli and Palestine/Sinai.
“We all have a reason to say ‘Thank You’ to this special generation”.