On the 12th January, 1915, Captain Schimmer attacked a Belgian camp at Luwungi, but the intended surprise was unsuccessful. Captain Zimmer and three Askari were killed and five wounded.
Then, on the 16th, 17th and 20th March small patrol skirmishes took place, and on the 20th May a Belgian post was surprised. There was thus incessant fighting, which continued in June and July. In August the enemy seemed to be increasing his forces in that region. The command on the Russissi was now taken over by Captain Schulz; the forces we had there now consisted of four field companies, part of the crew of the Moewe, and the Urundi Detachment, which about equalled one company. There were also two light guns there. On the 27th September Captain Schulz attacked Luwungi, when we were able to establish that the enemy lost fifty-four Askari killed, and we also counted seventy-one Askari hit. So the enemy’s losses amounted to about two hundred, as confirmed by native reports received later. We had four Europeans and twenty Askari killed, nine Europeans and thirty-four Askari wounded.
Owing to the nature of the country and the relative strengths, we were unable to achieve a decisive success on the Russissi. Only the Urundi Detachment and one field company were, therefore, left there; two companies left on the 18th and 19th December, 1915, to join Captain Wintgens in Ruanda; three others moved to the Central Railway.
On the 19th October the enemy met the 14th Reserve Company, and although outnumbering it by two to one, lost twenty Askari, while we had three Askari killed and twelve wounded. Although the Belgian main camp, which reliable natives reported to contain two thousand Askari, was so near, it was possible to reduce the troops on the Russissi in favour of other districts, since on both sides the conditions seemed unfavourable for an offensive. The Urundi Detachment and the 14th Reserve Company remained on the Russissi under Major von Langenn.
On Lake Tanganyika, at the beginning of the war, Captain Zimmer had collected about one hundred men of the Moewe, and in Usambara, about one hundred Askari; in addition, he had a few Europeans who were called up in Kigoma, also some one hundred Askari belonging to the posts in Urundi and from Ruanda (Wintgens)—all told, about four hundred rifles.
On the 22nd August, 1914, Lieutenant Horn, of the Moewe, commanding the small armed steamer Hedwig von Wissmann, fought a successful action against the Belgian steamer Delcommune. The captain of the Moewe, Lieutenant-Commander Zimmer, had gone to Kigoma with his crew, after destroying his ship, which had been blown up in August, 1914. The steamer Kingani, which had also been transported to the same place by rail from Dar-es-Salaam, and several smaller craft on Lake Tanganyika, were then armed and put in commission by Lieutenant-Commander Zimmer. He also mounted a 3·5-inch naval gun on a raft and bombarded a number of Belgian stations on the shore. He strongly fortified Kigoma itself, and developed it into a base for naval warfare on Lake Tanganyika.
On the 20th November, 1914, the Bismarckburg Detachment (half company), co-operating with the small armed steamers Hedwig von Wissmann and Kingani, drove off a Belgian company in the bay west of Bismarckburg, captured four ·43-inch machine guns and over ninety miles of telegraph wire, which was used to continue the line Kilossa-Iringa up to New Langenburg, a work which was, from a military point of view, extremely urgent.
Early in October attempts were made to complete the destruction of the Belgian steamer Delcommune, which was lying at Baraka, on the Congo shore, but without success. After bombarding her once more on the 23rd October, Captain Zimmer looked upon her as permanently out of action. On the 27th February, 1915, the crew of the Hedwig von Wissmann surprised a Belgian post at Tombwe, and captured its machine gun. One Belgian officer and ten Askari were killed, one severely wounded Belgian officer and one Englishman were captured. We had one Askari killed, one European mortally wounded, one Askari severely wounded.
In March, 1915, the Belgians made arrests on a large scale in Ubwari, the inhabitants of which had shown themselves friendly to us, and hanged a number of people.
According to wireless messages which we took in, several Belgian whale-boats were got ready on Lake Tanganyika during June, and work was being carried on on a new Belgian steamer, the Baron Dhanis. On our side the steamer Goetzen was completed on the 9th June, 1915, and taken over by the Force. She rendered good service in effecting movements of troops on Lake Tanganyika.