The boxes of pictures were being thrown away but keen photographer John saved them, developed them and has now tracked down the descendants of those in the snaps.
Civil servant John stashed them in his loft until he found them again while renovating three years ago.
John, from Bath, Somerset, started processing the pictures using his smartphone and online software and shared them on Twitter.
With the help of some internet detectives, he was able to date them to Edwardian times between 1900 and 1910.
Unlike many portrait photographs from the period, these snaps show a more relaxed side of life over a hundred years ago.
The black-and-white images show a wealthy family enjoying themselves playing golf, at the coast and on a variety of European holidays.
But John said it was the photos of young children playing with their pet dog that touched him the most.
John said: “I’ve always done film photography since I was little. I even had a darkroom in my bedroom.
“It’s always been a passion and that’s why I felt sorry for them being chucked away.
“You’d think people from the Edwardian times would be quite restrained and formal. But they’re just normal family photos of people messing around and kids having a great time.
“The pictures are a snapshot of Britain before the war started. A few years later it would have been mayhem.”
Thanks to a name of a village on the side of a box of pictures, John began to track down the mystery family.
He said: “The village was Yapton, West Sussex, and that was the key to everything.”
Eventually, he identified the people in the pictures as the Fletcher family.
The photographer was Sidney Fletcher, a wealthy banker, who had two sons, Dennis and Geoffrey, with his wife Annie.
Both boys survived the First World War but Dennis sadly died in an air accident in the Second World War.
His brother Geoffrey became a farmer in Somerset, which John believes is how the photos ended up there.
After some more sleuthing, he tracked down Sidney Fletcher’s great granddaughters, Tracey and Amanda Congdon, and was able to share the snapshots of their ancestry.
John said: “The history group ran a story about the photos in their quarterly magazine and the great-granddaughters discovered it by chance when researching their family history. They got in contact with the group who got in touch with me. They’re over the moon.
“The pictures were forgotten about but I’m really happy that they can be saved, thanks to modern technology like smartphones.”
John still has another box of photos to uncover, which he hopes will fill in the final gaps of the Fletcher family’s story.
Follow his progress, or perhaps even contribute, at The Unknown Photographer on Twitter.