A GRAVESEND army officer was freed from a German POW camp during the First World War to see his dying mother – and kept a promise to the Kaiser by returning, a historian has discovered.

Capt Robert Campbell was 29 when was captured just weeks after Britain declared war on Germany in July, 1914.

But after two years in Magdeburg prisoner of war camp the British officer received word from home his mother Louise Campbell was close to death.

He speculatively wrote to Kaiser Wilhelm II begging to be allowed home to visit his mother one final time.

Incredibly the German leader granted the request allowing Captain Campbell two weeks leave on the condition he keep his word as an army officer and return.

He returned to his family home in Gravesend in December 1916 and spent a week with his cancer-stricken mother.

He then kept his promise by taking the two day trip by boat and train back to his German prison where he stayed until the war ended in 1918. His mother passed away in February 1917.

The remarkable example of wartime honesty was uncovered by historian Richard Van Emden, 48, as he researched his new book.

But the author admits the act of chivalry was rare even for the bygone age of the Great War.

He said: "Capt Campbell was an officer and he made a promise on his honour to go back. Had he not turned up there would not have been any retribution on any other prisoners.

"What I think is more amazing is that the British Army let him go back to Germany. The British could have said to him 'you're not going back, you're going to stay here'.

"This was totally unique. I think it is such a unique example that I don't think you can draw any parallels. In my experience this is a one off and is one of those things that just tickles your fancy."

Capt Campbell's story has been told in Mr Van Emden's new book Meeting the Enemy: The Human Face of the Great War.