The appeal forms part of Archiving Remembrance, a heritage project supported by money raised by National Lottery players through The National Lottery Heritage Fund, which backs projects connecting people and communities with the UK's heritage.
The project will document the creation and development of the Arboretum, regarded as one of the UK's most significant millennium heritage projects.
The resulting archive will house oral histories, analogue and digital documents, ledgers, plans, journals, photographs, films and other material relating to its evolution as a visitor destination.
Working with past and present team members, supporters and individuals connected to the site, organisers hope to preserve the stories of those who helped shape it for future generations - from memories of early visits and development work to photographs, souvenirs and documents linked to events over the years.
The Archiving Remembrance team has been cataloguing and digitising material already held in the Arboretum's collection since May, marking 25 years since the site officially opened to the public. They are now inviting contributions from the wider public.
Aaron Rossi, exhibitions and heritage manager at the National Memorial Arboretum, said: "The Arboretum holds the collective memory of our nation, but the story of how this special place came to be is still being written.
"As we mark 25 years since opening to the public, we want to hear from the people who have helped shape the Arboretum's story.
“Whether you were involved in its early development, have volunteered or worked here, attended events, supported our growth, or simply have memories of visiting, we'd love to hear from you.
“We're particularly interested in photographs, documents, objects and memories that help tell the story of the Arboretum itself, its creation, development and impact over the past 25 years.
“Together, these contributions will help us preserve the history of this site and the people connected to it for future generations.”
Visitors can find out more about the project and meet members of the heritage team at the Arboretum's Heritage Hub, a pop-up space dedicated to the initiative, until 30 September.
There, the public can watch materials being catalogued and digitised and help identify people and moments from the site's early years.
Alongside gathering physical archive material, the project is also recording oral histories to preserve personal experiences connected to the site.
Archiving Remembrance will culminate in a special exhibition opening onsite later this autumn, followed by a publication exploring the Arboretum's heritage and the stories that continue to shape its future.
