structural:expansion, structural:reformatting, information:classification, information:extraction
Conflict with Great Britain

The British sent a mission under an Assyrian -born British subject, Hormuzd Rassam, who bore a letter from the Queen (in response to Tewodros' now three-year-old letter requesting aid). He did not bring the skilled workers as Tewodros had requested. Deeply insulted by the British failure to do exactly as they were asked, Tewodros had the members of the Rassam mission added to his other European prisoners. This last breach of diplomatic immunity was the catalyst to Britain launching the 1868 Expedition to Abyssinia under Robert Napier. He traveled from India, then a British colony, with more than 30,000 personnel (a force of 13,000 troops and 26,000 camp followers), which consisted of not only soldiers but also specialists such as engineers. Tewodros had become increasingly unpopular over the years due to his harsh methods, and many regional figures had rebelled against him. Several readily assisted the British by providing guides and food as the expeditionary force marched towards Magdala, where the Emperor had fortified the mountaintop.

The British force defeated the Abyssinian army at Arogye, on the plain facing Magdala, on 10 April 1868. With Tewodros' army so decisively defeated, many of his men began to desert and the emperor was left with only 4,000 soldiers. Tewodros II attempted to make peace. Napier responded with a message thanking him for this peace offering and stating that he would treat the Emperor and his family with every dignity. Tewodros II furiously responded that he would never be taken prisoner. The British shelled Magdala, which killed most of Tewodros's remaining soldiers. Tewodros released all the Europeans unharmed but ordered 300 Ethiopian prisoners to be flung over the cliff.

On 15 April 1868, as the British troops stormed the citadel of Magdala, Emperor Tewodros committed suicide rather than surrender.

A modern commentator states "When Tewodros preferred self-inflicted death to captivity, he deprived the British of this ultimate satisfaction and laid the foundation for his own resurrection as a symbol of the defiant independence of the Ethiopian."

He has been said to have used a pistol which he had used during fighting for unification during the era, though in reality he used a duelling pistol gifted to him by Queen Victoria and presented by Consul Cameron. Tewodros II was buried by the British troops at Magdala's Medhane Alem (Savior of the World) Orthodox Church under the name of Theodore II. In 2019 the National Army Museum announced the return to Ethiopia of a lock of Tewodros' hair, taken after his death in battle. Magdala was in the territory of the Muslim Oromo tribes who had long before taken it from the Amhara people; however Tewodros had won it back from them some years earlier. Two rival Oromos queens, Werkait and Mostiat, had both allied themselves with the British and claimed control of the conquered fortress as a reward. Napier much preferred to hand Magdala over to the Christian ruler of Lasta, Wagshum Gobeze, because if Gobeze were in control of the fortress, he would be able to halt the Oromos advance and assume responsibility for over 30,000 Christian refugees from Tewodros's camp. Yet as Gobeze was unresponsive to these overtures, much preferring to acquire Tewodros's cannons, and the two Oromo queens could not reach an arrangement, Napier decided to destroy the fortress. After a thorough medical examination which confirmed Tewodros' death as the result of suicide, the body was dressed and laid out in a hut. By the request of the Emperor's widow, the body was later buried in the Church of Magdala. Lieutenant Stumm, an eyewitness, described the discovery of Tewodros's body:

Climbing a narrow rock stairway, we advanced quickly toward a second gate, through which we passed without meeting resistance. About a hundred paces beyond it lay the half-naked body of the Emperor himself, who had taken his own life with a pistol shot. A strange smile was on the remarkably young and attractive-looking face, and I was struck particularly by the finely drawn, boldly aquiline nose.

After Tewodros has been buried, Napier allowed his troops to loot the citadel as a punitive measure; according to historian Richard Pankhurst, "fifteen elephants and almost 200 mules were required to carry away the booty". These became dispersed in museums and state collections across Europe, though some looted artifacts have been returned to Ethiopia. Tewodros II's family later moved the Emperor's remains to the Mahedere Selassie Monastery in his native Qwara, where they remain to this day. Tewodros had asked his wife, the Empress Tiruwork Wube, in the event of his death, to put his son, Prince Alemayehu, under the protection of the British. This decision was apparently made in fear that his life would be taken by any aspirant for the empire of Abyssinia. In accordance with these wishes, Alemayehu was taken to London where he was presented to Queen Victoria, who took a liking to the young boy. Alemayehu later studied at Cheltenham College, the Rugby School and the Royal Military Academy Sandhurst. However, both the Queen and Napier were later concerned with the subsequent development of the young prince who became increasingly lonely, unhappy and depressed during this time. In 1879, the prince died at the age of 19. He was buried near the royal chapel in Windsor with a funeral plaque placed to his memory by Queen Victoria.

On a curious side note, many of the hostages were unhappy with Napier's demand that they leave the country. Several hostages argued that they had long since become alienated from their old homeland in Europe and would no longer have any chance of building a new life for their families there. The German observer Josef Bechtinger, who accompanied the expedition, wrote:

Most of them, instead of thanking Providence for their final rescue – were not all happy with the new turn of events. They were indignant, upset, at having to leave Abyssinia. "What" they said, "are we supposed to do in Europe now, what are we supposed to do now with our wives and children back in our homeland – which has become alien to us? How are we supposed to live now among people who have alien to us and whom we no longer like? What are we supposed to live on?

Bechtinger reported that many of them eventually returned to their adopted country from Suez by way of Massawa.

Following some short squabbles for the throne after his death, Tewodros II was eventually succeeded by Yohannes IV as the next Emperor of Ethiopia.