The Rubens was a 3587grt steel screw steamer, launched from the William Gray shipyard on February the 9th, 1906, for the Bolton Steam Shipping Co. Ltd., of London. She was 343ft long, with a breadth of 49ft, depth of hold of 23ft, and was fitted with a 3-cylinder CMEW triple-expansion steam engine.
Unfortunately, when war broke out, she was in the German port of Hamburg, where she was immediately seized and her crew interned.
At this time, a number of German warships were stationed at naval bases around the world. One such ship, the light cruiser KONIGSBERG, under the command of Max Looff, was operating out of Dar-es-Salaam, the capital of German East Africa.
Her efforts to attack British and Allied shipping in the area were severely hampered by a lack of coal and the use of base facilities. However, two supply ships, Zeiten and Somali, kept her provided with coal, supplemented by the capture, on August 6th, of the Ellerman Lines City of Winchester, bound for London from Calcutta with tea and general cargo.
After attacking the port of Zanzibar on August 20th, and sinking the elderly British protected cruiser Pegasus, the Konigsberg retired up the Rufiji River for a much needed overhaul, and moored at the town of Salele. It was discovered that a number of engine parts needed replacing, and these had to be transported overland from Dar-es-Salaam. Effectively crippled, the Konigsberg was spotted by the British Cruiser Dartmouth on October 30th, which with two other British cruisers, set up a close blockade of the Rufiji River Delta, preventing the Konigsberg from leaving, even if she had been able to.
Conditions on the Königsberg soon began to deteriorate, many of her crew suffering from malaria with increasing shortages of food and medical supplies.
In an attempt to re-supply the ship, and at the same time provide guns and ammunition for the troops of Colonel von Lettow-Vorbeck’s Corps, the Rubens was converted to match the appearance of a Danish vessel, the Kronborg, and loaded a cargo of much-needed supplies, including 1600 tons of best steaming coal, guns, ammunition, food and medical supplies.
With suitably forged papers and a hand-picked crew of Danish-speaking German sailors under the command of Captain Carl Christiansen, she sailed on February 19th, 1915. By April 8th, she had rounded the Cape of Good Hope and was off the coast of Madagascar. Her captain now sent a wireless message to the Konigsberg, which was intercepted by the British.
On April 14th, the Kronborg approached Manza Bay, only to find the light cruiser Hyacinth waiting for her. The Hyacinth was a ‘Highfler’-Class cruiser, of 5,650 tons and had been built in 1898. She mounted eleven 6-inch guns as her main armament, with a further nine 12-pdrs., six 3pdrs. and also had two 18ins torpedo tubes. She was theoretically capable of 20 knots.
The following is an extract from HMS Hyacinth’s log:
4:10am: Hove to off Kilulu Channel to wait daylight.
4:45am: Proceeded inside reef.
4:50am: Stopped. Starboard engine broken down.
5:05am: Sighted smoke on port bow which proved to be enemy’s supply ship.
5:30am: Supply ship turned to starboard. Opened fire with 6 ins. but found she was out of range.
6:20 am-6:27am: Fired 6” across the land at steamer and apparently set her on fire.
6:40am: Turned into Mansa Bay firing at supply ship.
7:55am: Sent party with fire engine to supply ship.
9:10am: Opened fire with 6” and swept shore line to stop fire on the boats working at supply ship.
9:20am: Abandoned salvage work on supply ship. Recalled boats.
9:40am: Opened fire on supply ship with 6” lyddite.
9:50am: Swept shore line with 6 ins. shrapnel.
10:15am: Fires 6 ins. at supply ship and 12 pdr. at boats on shore and destroyed them.
10:30am: Supply ship well on fire in all holds and engine room. She had apparently settled on the bottom.
10:45am: Weighed and proceeded out of harbour.
Capt. Christiansen had run his ship ashore and ordered fires to be set in an attempt to fool the British into thinking the ship had been destroyed. Landing parties from Hyacinth did board the steamer and try to put out these fires, but were quickly driven back by gunfire from the shore, and soon afterwards the cruiser sailed out of the bay. The Germans managed to salvage almost all of the supplies from the Kronborg, with the exception of the coal and a small quantity of ammunition.
For the Konigsberg, it was all to no avail. The Royal Navy sent two Monitors, the Mersey and the Severn, to bombard the German cruiser, using aircraft to spot fall of shot. On July 11th, 1915, she was scuttled, her surviving crew members joining the German land forces.
The Konigsberg was partially salvaged in the early 1960s, her final remains eventually sinking into the riverbed. The surviving hull structure of the Kronborg, ex-Rubens, were finally refloated in 1956 and taken to the port of Dar-es-Salaam to be broken up.