Thomas Lennox Gilmour (1859–1936) was a British journalist, historian, and political observer who served as Private Secretary to Archibald Primrose, 5th Earl of Rosebery—a former British Prime Minister (1894–1895), Foreign Secretary, and leading figure in Liberal imperialist politics. Gilmour’s proximity to high-level diplomatic affairs and imperial policy gave him unique insight into the geopolitical rivalries of his time.

As an astute analyst of African-European relations, Gilmour traveled extensively and closely followed Ethiopia’s emergence as a sovereign African power during the colonial scramble. His firsthand documentation of Ethiopia’s political and diplomatic landscape, particularly its railway ambitions under Emperor Menelik II, culminated in Abyssinia: The Ethiopian Railway and the Powers, first published in 1906. This rare and revealing account—now republished as Ethiopia: The Railway, the Powers, and the Start of the First World War—a critical historical source for understanding the imperial entanglements that reshaped Africa and helped precipitate the First World War.