England's highest mountain was gifted to the National Trust by landowner Lord Leconfield in 1919 in "perpetual memory of the men of the Lake District who fell for God and King, for freedom, peace and right in the Great War".
A further 12 peaks - Lingmell, Broad Crag, Great End, Seathwaite Fell, Allen Crags, Glaramara, Kirk Fell, Great Gable, Green Gable, Base Brown, Brandreth and Grey Knotts - were donated by the Fell and Rock Climbing Club in 1923.
In a dedication ceremony dubbed a "service in the clouds" on top of Great Gable in 1924, writer and mountaineer Geoffrey Winthrop Young, who had lost a leg during the war in Italy, said "we are met today to dedicate this space of hills to freedom".
Together the donations were one of the largest the trust has ever received, triggered a series of endowments to the trust, and today mean hundreds of thousands of people can freely walk the mountains every year, it said.
A hundred years on from the final year of the First World War, the trust is planning a series of commemorations "rededicating" the mountains, including rebuilding a summit cairn on Scafell Pike.
Rangers will camp out on the peak to carry out the rebuilding work, which includes resetting the memorial plaque within the walls of the cairn.
The re-dedication of the mountains will also see work to repair paths on Scafell Pike and Great Gable, while musicians and choirs will be brought together for a "song cycle" project across the 12 peaks.
A Where Poppies Blow exhibition at Wordsworth House, Cockermouth, will explore the role of nature in helping soldiers through the horrors of war.
And on Armistice Day in November, the National Trust will light a beacon on top of Scafell Pike, as Lord Leconfield did on Peace Day 1919, shortly before he donated the mountain to the conservation charity.
Marian Silvester, general manager for the National Trust, said: "Millions of people visit the Lake District each year but few are familiar with the story behind these mountains, which we are extremely proud to look after.
"By rededicating the peaks, not only are we remembering the past, but looking to the future to ensure this inspiring landscape can be enjoyed by generations to come."
British mountaineer Sir Chris Bonington, who served for several years in the Royal Tank Regiment, said: "I can't help but be inspired every time I return home to the Lakes, by its wildness and charm, and the challenges it presents.
"Beyond its staggering beauty, the Lake District has a rich cultural history and a web of fascinating stories."
He said it was important that the millions of visitors to the national park, which was made a World Heritage Site in 2017, played their part alongside organisations such as the National Trust to look after the fells for the future.