The 1886 Treaties and the "Rose-Colored Map": Portugal’s Imperial Ambitions in Africa

In 1886, Portugal signed two treaties with France and Germany, formally delimiting colonial boundaries and securing international recognition of Portuguese sovereignty over vast interior territories between Mozambique and Angola. These agreements reinforced Portugal’s claim to a continuous east-west corridor across Africa, a vision that would become central to Portuguese imperial ambitions.

The "Rose-Colored Map" and Portuguese Expansion Efforts

• The Portuguese claim to this territory between Mozambique and Angola was visually represented in a map annexed to the treaty with France, where the claimed lands were colored red—a depiction that would later be known as the "rose-colored map" (Mapa Cor-de-Rosa).
• To substantiate this claim, Portugal organized successive expeditions into the interior, attempting to establish effective occupation in line with the principles set by the Berlin Conference (1884–1885).

British Rivalry and the Cape-to-Cairo Railway

While Portugal sought to consolidate its territorial ambitions, Britain had its own imperial objectives in the region. Under the leadership of Cecil Rhodes, the British were simultaneously exploring the interior from south to north, aiming to establish a British-controlled corridor from Cape Town to Cairo, linked by a transcontinental railway.

This conflict of interests between Portugal and Britain would soon escalate, leading to a diplomatic crisis that would culminate in the 1890 British Ultimatum, forcing Portugal to abandon its territorial aspirations in favor of British expansionism.