Tanga, situated only 80 kilometres (50 mi) from the border of British East Africa (modern-day Kenya), was a busy port and the ocean terminal of the important Usambara Railway, which ran from Tanga to Neu Moshi at the foot of Mount Kilimanjaro.
Tanga was initially to be bombarded by British warships, but this part of the plan was scrapped.
An agreement was in place guaranteeing the neutrality of the capital Dar es Salaam and Tanga, but now the accord was modified and it seemed "only fair to warn the Germans that the deal was off."

Instead, the British resolve to capture German East Africa was to be implemented with an amphibious attack on Tanga.
Unlike the plan on paper, however, the attack turned into a debacle.
On 2 November 1914, the British protected cruiser HMS Fox arrived.
The ship's commander, Captain Francis Wade Caulfeild, went ashore giving Tanga one hour to surrender and take down the imperial flag.
Before departing, he demanded to know if the harbor was mined; it was not, but he was assured that it was.
After three hours, the flag was still flying and Fox departed to bring in the Force "B" convoy of fourteen troop transports.
This gave time for both the Schutztruppe and the citizens of Tanga to prepare for an attack.
The German commander, Lieutenant Colonel Paul Emil von Lettow-Vorbeck, rushed to Tanga.
He reinforced the defences (initially only a single company of Askaris) with troops brought in by rail from Neu Moshi, eventually numbering about 1,000 in six companies.
His second-in-command was former German East Africa Company Captain Tom von Prince.
Tanga, situated only 80 kilometres (50 mi) from the border of British East Africa (modern-day Kenya), was a busy port and the ocean terminal of the important Usambara Railway, which ran from Tanga to Neu Moshi at the foot of Mount Kilimanjaro. Tanga was initially to be bombarded by British warships, but this part of the plan was scrapped. An agreement was in place guaranteeing the neutrality of the capital Dar es Salaam and Tanga, but now the accord was modified and it seemed "only fair to warn the Germans that the deal was off."
Instead, the British resolve to capture German East Africa was to be implemented with an amphibious attack on Tanga. Unlike the plan on paper, however, the attack turned into a debacle. On 2 November 1914, the British protected cruiser HMS Fox arrived. The ship's commander, Captain Francis Wade Caulfeild, went ashore giving Tanga one hour to surrender and take down the imperial flag. Before departing, he demanded to know if the harbor was mined; it was not, but he was assured that it was. After three hours, the flag was still flying and Fox departed to bring in the Force "B" convoy of fourteen troop transports. This gave time for both the Schutztruppe and the citizens of Tanga to prepare for an attack. The German commander, Lieutenant Colonel Paul Emil von Lettow-Vorbeck, rushed to Tanga. He reinforced the defences (initially only a single company of Askaris) with troops brought in by rail from Neu Moshi, eventually numbering about 1,000 in six companies. His second-in-command was former German East Africa Company Captain Tom von Prince.
Battle of Tanga