Historical diplomatic records reveal how President Franklin D. Roosevelt negotiated directly with Portuguese leader António de Oliveira Salazar in 1944, connecting American military ambitions in the Atlantic with Portugal’s interests in Japanese-occupied Timor.
The construction of an American air base on the Azorean island of Santa Maria during World War II was the result of high-level negotiations between Washington and Lisbon that extended far beyond the strategic needs of the Atlantic. Historical diplomatic documents examined in a report by Paulo Hugo Viveiros, published in Diário dos Açores, reveal how the United States secured access to the island in 1944 while Portugal sought recognition of its interests in Timor, then occupied by Japanese forces. The negotiations involved direct correspondence between President Franklin D. Roosevelt and Portuguese Prime Minister António de Oliveira Salazar, demonstrating how a small Atlantic island became part of a much larger diplomatic struggle spanning Europe, the Atlantic, and the Pacific.
By the summer of 1944, American military planners were preparing for intensified operations against Japan. Moving aircraft, personnel, and equipment across enormous distances required strategically positioned airfields capable of supporting transoceanic operations. Santa Maria, situated at the southeastern edge of the Azorean archipelago, offered a valuable location for refueling, maintenance, and logistical support. Yet Portugal’s official neutrality presented a diplomatic obstacle, requiring Washington to negotiate permission rather than simply establish a military installation.
On July 18, 1944, Roosevelt personally wrote to Salazar requesting authorization to proceed with construction. The correspondence, preserved in the official Foreign Relations of the United States collection, indicates that American technical assessments had already been completed and that Washington was anxious to begin work before unfavorable weather conditions complicated construction. Five days later, Salazar responded favorably, referring to arrangements involving Pan American Airways, the American aviation company that participated in developing the airfield. The involvement of a civilian airline provided a practical framework for a project whose ultimate purpose was military.
Portugal’s cooperation, however, was closely connected to another wartime concern: the future of Portuguese Timor. Japanese forces had occupied the territory in 1942, despite Portugal’s neutrality, and Lisbon wanted to participate in its eventual recovery. Diplomatic records show that Portugal had communicated this intention to Britain as early as June 1943. By July 1944, British and American authorities had accepted, in principle, the possibility of Portuguese participation in operations involving Timor, although military arrangements remained unresolved.
The negotiations created two possible forms of Portuguese participation in the Allied war effort against Japan. Direct participation would involve Portuguese military forces in an eventual operation to recover Timor. Indirect participation would consist of making Santa Maria available to the United States for the movement of aircraft and military personnel toward the Pacific theater. A Portuguese diplomatic memorandum dated August 24, 1945, explicitly described these two dimensions of cooperation, establishing the connection between the Atlantic air base and Lisbon’s ambitions in Southeast Asia.
The agreement authorizing American military use of Santa Maria was formally signed in Lisbon on November 28, 1944. The following day, Acting United States Secretary of State Edward Stettinius Jr. informed Roosevelt that Portugal had instructed its authorities in the Azores to transfer the installation to the American Army for immediate use. The documents establish that Santa Maria was not simply an airport occasionally used by American aircraft, but a military facility made available through a specific diplomatic agreement.
The American presence transformed the island’s infrastructure and international significance. Construction and military operations brought new facilities, equipment, communications systems, and logistical activity to a territory that had previously occupied a relatively modest position in international aviation. Santa Maria became part of the network supporting American transoceanic movements, establishing an aviation infrastructure that would later prove essential to the island’s civilian development.
The war ended before the planned military recovery of Timor could take place. Germany surrendered in May 1945, followed by Japan in August, eliminating the need for an Allied reconquest under the arrangements previously discussed. Nevertheless, Portuguese diplomats continued to emphasize their country’s contribution to the war against Japan, including preparations for a Portuguese expeditionary force and the granting of American access to Santa Maria. Lisbon sought to ensure that this cooperation would strengthen Portugal’s position in postwar discussions concerning the Far East.
The end of hostilities also raised a new question: who would control the airfield? Portugal wanted to recover direct authority over the installation, while the United States hoped to preserve access to the strategically valuable Azores. A classified American proposal dated May 21, 1946, envisioned joint administration of Santa Maria, continued American operational privileges, and arrangements covering communications, meteorological services, navigation, and military support. Although the proposal recognized Portuguese sovereignty, it sought to establish a continuing American role in managing the airport.
A subsequent agreement signed in Lisbon on May 30, 1946, established the formal transfer of the Santa Maria and Lajes airfields to Portuguese authorities on June 2. The agreement, preserved in the United Nations Treaty Series, also permitted American and British military aircraft supporting occupation forces in Germany and Japan to transit through Lajes for 18 months. Until a Portuguese military aviation unit was established there, Santa Maria could also be used for that purpose.
American interest in the archipelago did not disappear with the transfer. Diplomatic correspondence from July 1946 reveals continued discussions over the interpretation of the agreements and Washington’s desire to secure more extensive rights. A particularly revealing American proposal, classified Top Secret and dated July 24, 1946, contemplated military facilities at Lajes, Santa Maria, and potentially other locations in the Azores and Cape Verde, with rights extending for as long as 99 years. This was a negotiating proposal rather than an agreement accepted by Portugal, but it illustrates the strategic importance American officials continued to assign to the islands as the postwar international order emerged.
For Santa Maria, the most enduring consequence was the airport itself. Originally conceived to serve wartime military requirements, the facility became an important stopover for international civilian aviation during the decades when aircraft crossing the Atlantic required intermediate refueling and technical support. The island entered global aviation networks, creating new economic activity and connections with Europe and North America. Although advances in aircraft technology eventually reduced the need for transatlantic stopovers, the airport remained a defining feature of Santa Maria’s modern history.
The American military presence in the Azores subsequently became concentrated primarily at Lajes Air Base on Terceira, but Santa Maria retained a place in bilateral defense arrangements. The 1995 Portugal–United States Defense Cooperation Agreement, for example, identified Santa Maria Airport as a primary alternate to Lajes.
The historical significance of Santa Maria’s wartime transformation extends beyond the construction of an airfield. As the diplomatic records demonstrate, the island’s strategic location brought it into negotiations involving American military planning, Portuguese neutrality, British interests, and the future of a colonial territory thousands of miles away. The history also illustrates the competing priorities of the governments involved: Washington sought military mobility, while Lisbon attempted to protect its sovereignty and advance its interests in Timor.
More than eight decades later, Santa Maria’s airport remains a physical reminder of those decisions. What began as a wartime military project became a lasting element of the island’s economic and social development, connecting a small Azorean community to the wider history of international aviation and transatlantic diplomacy.
The story, reconstructed through diplomatic correspondence and historical photographs, demonstrates how the geography of the Azores repeatedly placed the archipelago at the intersection of global events. In 1944, Santa Maria was far removed from the principal battlefields of World War II, yet its location made it part of decisions taken at the highest levels of American and Portuguese government. The island’s modern aviation history was shaped not only by the demands of war, but also by negotiations concerning sovereignty, strategic influence, and the future of territories on opposite sides of the world.
Based on historical reporting by Paulo Hugo Viveiros in Diário dos Açores, drawing on United States diplomatic archives and international treaty records.
Photo credits: LPAZ/Fold3.com
Diário dos Açores, and Novidades – the islands and the diaspora- both, extend our appreciation to the Municipality of Vila do Porto for its cooperation and to the LPAZ Association for providing the historical photographs accompanying this report on the American military presence on the island of Santa Maria during World War II.