Military service details about King George VI which feature comments on his stammer and general ill-health have been released by the Public Records Office.

They reveal that his general conduct aboard HMS Collingwood was regarded by senior officers as merely "satisfactory".

However, that ship's captain noted that the future king, then Prince Albert, "promises well" but was "nervous of speech".

In August 1914, it was recorded that he was making "favourable progress" despite various sick leave entries, including a month spent at Balmoral in September 1915.

Battling monarch

On the eve of the First World War Battle of Jutland, Prince Albert was in the Collingwood's sick bay, incapacitated by a surfeit of soused herring.

He nonetheless managed to man his gun turret and fought throughout the engagement - the last British monarch to see action in war.

He was commended in the London Gazette for his part in the battle.

After his time on HMS Collingwood, he spent some time on the staff of the Commander in Chief, Portsmouth, Sir Stanley Colville, who described the future king as "very zealous and hardworking".

The Public Records Office has also disclosed the Earl Mountbatten of Burma's records from 1920 when he was a midshipman in the Royal Navy.

Rear Admiral Halsey noted he "will make a good officer, plenty of common sense if he would use it, but is too casual".