The day before the attack, Commander Max Looff of SMS Konigsberg was coaling in the Rufiji River delta on the German East African coast when coast watchers brought word that a British warship had entered Zanzibar harbour. Looff saw opportunity. His ship, built in 1905 and armed with ten 10.5-centimeter quick-firing guns, was faster and better armed than anything the British had nearby. He ordered an immediate sortie on the afternoon tide. Meanwhile, HMS Pegasus -- a protected cruiser built in 1897, carrying eight four-inch guns and a crew of 234 -- sat at anchor in Zanzibar undergoing engine and boiler repairs. She had just left the company of HMS Astraea and was in no condition to fight. The only warning system the British had was HMS Helmuth, a captured German tug armed with a single three-pounder gun, posted as a picket ship at the harbour entrance.

Konigsberg entered from the southern approaches at dawn. She fired a few warning shots past Helmuth, which could neither stop the German cruiser nor raise an alarm in time. At a range of 9,000 yards, Konigsberg opened fire on Pegasus with full salvos. For twenty minutes, the British ship sat motionless, her crew desperately trying to raise steam while shells tore into her decks. Pegasus did raise the White Ensign and returned fire, but her shells fell short -- Konigsberg stayed at least 2,000 yards beyond the range of Pegasus's guns. Not a single British round struck the German ship. As Konigsberg closed to 7,000 yards, the damage became catastrophic. Pegasus was holed near the waterline and began flooding. Captain John Ingles struck his colours and ordered his crew to abandon ship. She sank later that day. Thirty-eight British sailors died; another fifty-five were wounded, most of them caught on the open deck.

The hospital ship Gascon and the merchant vessel SS Clan Macrae pulled survivors from the water. Twenty-four of the dead were buried in a mass grave at the naval cemetery on Grave Island in Zanzibar harbour. Fourteen others were interred in the town cemetery before being moved in 1971 to the Dar es Salaam war cemetery. Staff Surgeon Alfred J. Hewitt remained on Pegasus's deck from the first salvo to the last, treating the wounded under fire -- Captain Ingles cited his courage in his official report. The British salvaged six of Pegasus's guns from the wreck and put them to use in the East African land campaign, a small act of recovery from a humiliating defeat. Helmuth, the picket tug, survived with minor damage, though one crew member -- a local African working in the engine room -- was killed.

Konigsberg's victory was clean but short-lived. One of her main engines failed shortly after the battle, and with the British watching Dar es Salaam, Looff had no choice but to retreat deep into the Rufiji River delta to await spare parts overland. The British discovered her hiding place and threw a blockade around the delta that would last for months. In July 1915, the Royal Navy brought up two shallow-draft monitors and pounded Konigsberg in the Battle of the Rufiji Delta, damaging her beyond repair. The crew scuttled their ship in the river mud, but the story did not end there -- her guns were salvaged and mounted on land carriages, fighting alongside German colonial forces throughout the East African campaign under the legendary Paul von Lettow-Vorbeck. The wreck of Pegasus rested in Zanzibar harbour for decades. The wreck of Konigsberg settled into the Rufiji delta mangroves. Two warships, destroyed within months of each other, their guns repurposed, their crews scattered across a continent at war.