Five letters and five postcards written by one Albert Paulsen are to sell in Wellington, New Zealand.
The young naval officer's letters are written to his love Emma Mayer about how much he wants to come home to her, and what the prisoners do to pass the long days.
Paulsen had been captured in 1914, when New Zealand took control of German Samoa.
Each of the 10 items is estimated to sell for NZ$3,000 ($2,100).
Paulsen wrote the letters from Motuihe Island off Auckland and/or Somes Island off Wellington.
In fact he did escape in 1917, along with officer Count Felix von Luckner and some other men. They stole a motorboat and travelled 1,000 miles in it before recapture.
The letters are being offered for auction by philatelist Walter Paterson, who picked them up as part of a collection of post related memorabilia.
The collection originated in Europe, though Paterson bought it from an American.
One unique piece is an envelope which held a letter sent from one German POW to another (One K Rudolph to a Klaus Klink).
Rudolph, like Paulsen, was held on Motuihe, whilst Klink was in New South Wales, Australia. It's one of very few examples of letters written between POWs in different countries.
The auction takes place later this week.