Arquivo Diplomático e Biblioteca do Ministério dos Negócios Estrangeiros

The Portuguese Diplomatic Archive, managed by the Diplomatic Institute under the Ministry of Foreign Affairs (MNE), is responsible for preserving and providing access to permanent documentation detailing Portugal's foreign policy since the restoration of independence in 1640. Its historical archives span approximately 5,000 linear meters and comprise three primary collections: MNE records from internal and external services (including embassies, consulates, and international missions), treaties and international acts dating from 1839 to the present, and acquired personal archives of notable diplomats and politicians such as Franco Nogueira and Andrade Corvo. Additionally, it houses inherited documents from the former Ministry of Overseas Territories. Historically, the archive traces its origins to the 1736 creation of the Secretary of State for Foreign Affairs and War. Significant portions of early records were lost in the 1755 Lisbon earthquake. Over the centuries, institutional reorganizations and conflicts caused further documentation loss and fragmentation, leading to major transfers of records to the National Archive Torre do Tombo, including a large-scale transfer in 1950 for documents dating up to 1850. Initially restricted to administrative use, the archive opened to historical research in 1921, with public reception services established in 1965. Portugal's entry into the European Union accelerated public access, leading to a formalized consultation system in 1986. A 1987 regulation established a 30-year rule for document consultation, officially renamed the institution as the Diplomatic Historical Archive, and created the Selection and Declassification Commission to manage its extensive heritage.