John Mountjoy Holt – Mercantile Marine - S.S. Algarve

Third Engineer John Mountjoy Holt – Mercantile Marine, S.S. Algarve

Early Life and Family Background

Alexander George Holt and Emily Mountjoy
marriage certificate
St. John church, Richmond, Surrey

John Mountjoy Holt was born in 1896, in Ireland, the son of Alexander George Holt and Emily Mountjoy, who were married in 1896 at St. John Church, Richmond, Surrey.

1901 Census

At the time of the 1901 Census, the Holt family were residing at 146 Mackintosh Place, Roath, Cardiff. Alexander, born in Worcestershire, aged 32, was employed as a Dental Surgeon’s Assistant, while his wife Emily, born in London, was 33 years old. Their children were Alexander G. (8), John M. (5), Norman D. (2), and Cecil R. (1). Also recorded in the household was Jane M. Holt (33), listed as a visitor.

In the years that followed, the family moved west to Swansea, eventually settling at 106 St. Helen’s Road, where they became part of the city’s long-standing maritime community.

Service and Sacrifice

Following his education, John Holt pursued a maritime career, training as a Marine Engineer and joining the Mercantile Marine during the First World War. By 1917, he was serving as Third Engineer aboard the S.S. Algarve, a British cargo steamship engaged in the hazardous task of transporting supplies essential to Britain’s survival during wartime.

On 20^th October 1917, the Algarve was torpedoed and sunk by a German submarine while sailing through the English Channel. The attack was sudden and devastating, and Third Engineer John Mountjoy Holt, aged just 21, was among those lost at sea.

The S.S. Algarve

The S.S. Algarve was a British steam cargo vessel, built in 1899, and engaged in carrying general cargo and supplies vital to the war effort.

On 20^th October 1917, while sailing in the English Channel, approximately 15 miles west-south-west of Portland Bill, Dorset, the Algarve was torpedoed without warning by the German submarine UB-38. The explosion was catastrophic, and the ship sank rapidly, resulting in the deaths of more than twenty crew members, including Third Engineer John Mountjoy Holt and First Mate Edward Brooks, aged 44.

The sinking of the Algarve took place during the height of Germany’s campaign of unrestricted submarine warfare, a strategy intended to blockade Britain by destroying all shipping—military and civilian alike—within its supply routes. The Algarve’s loss stands as a stark reminder of the peril faced daily by those who worked in the Merchant Navy, keeping the nation’s vital trade and resources flowing.

The German Submarine UB-38

The UB-38 was a Type UB II submarine of the Imperial German Navy, built by Blohm & Voss, Hamburg, and commissioned on 18 July 1916. Compact but highly effective, the vessel displaced 274 tons surfaced and 303 tons submerged, measured 36.9 metres in length, and carried a crew of 23 men.

Armed with two 50 cm torpedo tubes, an 8.8 cm deck gun, and capable of carrying up to six torpedoes, UB-38 was a formidable weapon despite her small size. She could reach speeds of 9 knots on the surface and nearly 6 knots submerged.

Throughout her brief but destructive career, UB-38 conducted 21 patrols and was credited with sinking 47 merchant vessels, with a combined tonnage exceeding 47,000 tons. Among her victims was the S.S. Algarve, sunk on 20^th October 1917 in the English Channel.

The submarine herself met a violent end only a few months later, on 8 February 1918, when she struck a mine in the English Channel while attempting to evade British destroyers. The explosion destroyed the vessel, and all hands were lost.

The short but deadly career of UB-38 epitomises the intense and unforgiving nature of the undersea war, which claimed thousands of merchant seamen’s lives — men like John Mountjoy Holt, who served faithfully below deck to keep their ships running amid constant danger.

Commemoration

S.S. Algarve
Tower Hill Memorial, London
credit - Benjidog Historical Research Resources:
The Merchant Navy Memorial

Third Engineer John Mountjoy Holt is commemorated on the Tower Hill Memorial, London — the national monument honouring those of the Merchant Navy and Fishing Fleets who died during both World Wars and have no known grave but the sea.

Legacy

Though he was only 21 years old, John Holt’s service stands as a testament to the courage and endurance of Swansea’s maritime men. His life and death form part of a much larger story — one of sacrifice, professionalism, and quiet heroism among those who kept Britain supplied during one of the darkest chapters of its history.