By 1869 David Livingstone — missionary, abolitionist, and Britain’s sainted explorer — had been out of contact in Central Africa for years, chasing a wrong theory of the Nile’s source through the lake country, repeatedly robbed, sick, and reduced to dependence on the Arab-Swahili slave traders whose commerce he had spent his life denouncing. Rumours had him dead. The New York Herald’s proprietor scented the century’s scoop and gave a hungry Welsh-born reporter a blank cheque and a two-word brief: find him.

Henry Morton Stanley — born John Rowlands in a Denbigh workhouse, self-reinvented in America through a career that included both sides of the Civil War — assembled nearly 200 porters at Zanzibar in 1871 and drove inland with a ruthlessness that became his signature: through fever (he nearly died repeatedly), swamps, a regional war he had to skirt, and floggings and desertions duly recorded. On 10 November 1871 (the date is conventional; his own accounts disagree), his column marched into Ujiji on Lake Tanganyika under the Stars and Stripes — to find a frail, white-bearded man in a blue cap coming out to meet the commotion.

”Dr Livingstone, I presume?”

So Stanley reported the greeting, and the world adopted it instantly — the drawing-room formality, absurd and perfect, in the heart of Africa. It may never have been said: the page covering the meeting has been torn from Stanley’s diary, Livingstone’s own account records the joy but no such phrase, and biographers suspect the awkward Stanley composed his immortal line at the writing desk. The torn page — whether hiding banality or fabrication — is its own monument to Victorian image-making.

What is certain: the two men, oddly matched, grew devoted. Stanley’s supplies revived Livingstone; they explored the north of the lake together (settling that it did not feed the Nile); and Stanley left after four months, carrying dispatches and journals that made both of them world-famous — and himself, to his lifelong resentment, widely disbelieved and mocked by the geographical establishment until the documents proved him.

Diverging legends

Livingstone refused to come home. Still chasing his wrong Nile, he died in May 1873 at Chitambo’s village; his companions Chuma and Susi buried his heart under a mpundu tree and carried his salt-dried body and papers over 1,500 kilometres to the coast — one of exploration’s great acts of fidelity — for burial in Westminster Abbey. His death-bed image powered the missionary and anti-slavery surge that Europe soon alchemised into conquest.

Stanley turned explorer outright — his later expeditions were epics of achievement and brutality — and then hired out his skills to King Leopold II, laying the groundwork of the Congo Free State: the century’s most famous handshake thus connects, in two careers, the map’s last blank spaces and the Scramble that filled them with flags.