In 1951, São Tomé and Príncipe existed as an overseas province of Portugal, and its currency situation was entirely dictated by the colonial metropole. The islands used the Portuguese São Tomé and Príncipe escudo (STPE), which was pegged at par with the Portuguese escudo (PTE). This meant the local currency had no independent monetary policy; its value and supply were directly controlled by Lisbon, primarily to facilitate the export of the colony's main products, cocoa and coffee, to Portugal.
The monetary system was designed to integrate the colony tightly into Portugal's economic sphere. All foreign exchange earnings from exports were managed through Portuguese banks, particularly the Banco Nacional Ultramarino, which acted as the central bank for Portugal's overseas territories. This structure ensured that Portugal could access foreign currency (like sterling or dollars) earned by the colony's lucrative plantation economy, while the islands themselves remained dependent on imported goods, often from Portugal.
Consequently, the currency situation in 1951 reflected the islands' status as a plantation economy and a captive market. There was little financial infrastructure for local development, and the fixed exchange rate system primarily served Portuguese commercial interests. This economic subordination, characteristic of the late colonial era, would later become a point of contention as movements for economic self-determination and eventual political independence gained momentum in the decades that followed.