HMS H6, was a British H-class

British H class submarine

The British H class submarines were Holland 602 type submarines used by the Royal Navy. The submarines constructed for the British Royal Navy between 1915 and 1919 were designed and built in response to German boats which mined British waters and sank coastal shipping with ease due to their small...

 submarine

Submarine

A submarine is a watercraft capable of independent operation below the surface of the water. It differs from a submersible, which has more limited underwater capability...

 of the Royal Navy

Royal Navy

The Royal Navy is the naval warfare service branch of the British Armed Forces. Founded in the 16th century, it is the oldest service branch and is known as the Senior Service...

 built by Canadian Vickers & Co. during World War I

World War I

World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...

.

History

She was completed on 10 June 1915 and was commissioned by the Royal Navy the same year. However, her service in the Royal Navy was short. On 19 January 1916 she ran aground near the Dutch island of Schiermonnikoog

Schiermonnikoog

Schiermonnikoog is an island, a municipality, and a national park in the northern Netherlands. Schiermonnikoog is one of the West Frisian Islands, and is part of the province of Friesland....

 after which she was interned by the Dutch Navy. On 4 May 1917 an agreement was reached to sell H6 to the Netherlands.

Dutch service

The Dutch Navy renamed the H6 to Hr.Ms. O 8 and refitted her with knowledge gained from the interned German submarine . After UC-8 was bought from Germany the O 8 was equipped with the s Zeiss periscope. During maintenance in October 1921, O 8 sank in the harbour at Den Helder

Den Helder

Den Helder is a municipality and a city in the Netherlands, in the province of North Holland. Den Helder occupies the northernmost point of the North Holland peninsula...

. Because only minor damage was sustained, she was repaired and continued service. In the summer of 1925 O 8 together with the K XI, Jacob van Heemskerk, Tromp, Z 3 and Z 5 were part of an exercise in the Baltic Sea

Baltic Sea

The Baltic Sea is a brackish mediterranean sea located in Northern Europe, from 53°N to 66°N latitude and from 20°E to 26°E longitude. It is bounded by the Scandinavian Peninsula, the mainland of Europe, and the Danish islands. It drains into the Kattegat by way of the Øresund, the Great Belt and...

.

During the German attack on the Netherlands

Netherlands

The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...

 at the start of the Second World War the O 8 was still in Dutch service. Because of her old age it was decided to scuttle her.

German service

After the surrender of the Netherlands the German forces were able raise the O 8 and found her almost fully intact.

Germany took the O 8 into service as U-D1 and transferred her from Den Helder to Kiel

Kiel

Kiel is the capital and most populous city in the northern German state of Schleswig-Holstein, with a population of 238,049 .Kiel is approximately north of Hamburg. Due to its geographic location in the north of Germany, the southeast of the Jutland peninsula, and the southwestern shore of the...

. In Kiel she was used as training ship to train crews for the German U-boat

U-boat

U-boat is the anglicized version of the German word U-Boot , itself an abbreviation of Unterseeboot , and refers to military submarines operated by Germany, particularly in World War I and World War II...

s. Because of her old age she was decommissioned on 23 November 1943. On 3 May 1945, she was scuttled in the harbor at Kiel.