Portugal was one of the founding members of NATO in 1949. For more than two decades, Portugal's material contribution to the alliance was marginal. Its armed forces were preoccupied with the fighting in Africa, and its efforts to maintain a colonial empire alienated it from the other members of the alliance. Nevertheless, its contribution in the form of strategically located bases and other military facilities was substantial. Major air bases and ports on the Portuguese mainland were deemed vital for rapid reinforcement and sea resupply of NATO forces on the continent. Control of Madeira was considered crucial for keeping the North Atlantic routes to the Straits of Gibraltar open for allied operations. The Azores provided essential refueling facilities for the rapid deployment of forces to Central Europe, the Mediterranean and the Middle East, as well as a key base for antisubmarine tracking and naval surveillance.

In the immediate postrevolutionary period when leftist ideology was in the ascendancy in the military, the question of Portugal's continued active participation in the alliance came into question. In 1975 Portuguese representatives absented themselves from highly classified NATO discussions. By 1980, however, Portugal had returned to full participation, rejoining NATO's Nuclear Planning Group and again taking part in NATO exercises. The establishment of a pro-Western democratic government, followed by the accession of Portugal to the European Community (EC) in 1986, inspired renewed interest in an active role in the alliance. The desire to provide the armed forces with a meaningful military mission after the African operations ended and to divert them from further involvement in civilian politics were additional factors in Portugal's willingness to undertake fresh NATO commitments. Portugal accordingly accepted the obligation to equip the First Composite Brigade to be at the disposal of the Supreme Allied Commander Europe (SACEUR) and agreed to increase its surveillance and control over a large sector of the eastern Atlantic by acquiring modern frigates and reconnaissance aircraft.

The Iberian Atlantic Command (IBERLANT), a major subordinate command under the Supreme Allied Commander Atlantic (SACLANT) located at Norfolk, Virginia, had its headquarters at Oeiras, near Lisbon. Since 1982 the IBERLANT commander has been Portuguese, a vice admiral with a staff of about sixty-five officers and 200 enlisted personnel mainly from Portugal, the United States, and Britain. IBERLANT encompassed the area extending from the northern border of Portugal southward to the Tropic of Cancer and approximately 1,150 kilometers seaward from the Straits of Gibraltar. Madeira was within IBERLANT's area, as were the Azores after transfer from NATO's Western Atlantic Command (WESTLANT) to meet Portuguese concerns.

The IBERLANT commander had no permanently assigned combat forces in peacetime. The IBERLANT staff carried out planning and conducted exercises to ensure the headquarters' readiness to assume command and logistic support of forces that would be assigned in a period of tension or 86a r war. In addition to the administrative facilities and underground command post at Oeiras, IBERLANT had extensive communications links with SACLANT at Norfolk and other command posts. Other NATO facilities in Portugal included ammunition and fuel depots and strategic reserves at Lisbon and a reserve airport at Ovar near Porto. NATO also occupied a portion of the Montijo Air Base for the same purpose and had fuel storage areas and access to the air base in the Azores. The Portuguese navy participated in exercises with other NATO fleets, particularly those involving protection of resupply convoys in the IBERLANT area.

When Spain became a member of NATO in 1982, Portugal was concerned that a reorganization of the NATO command structure might follow. Portuguese misgivings focused on the possibility that an integrated Iberian command would be formed under a Spanish commander and that Spain might be entrusted with security tasks within the area of Portuguese territories for which the Portuguese armed forces were not yet fully equipped. After Spain's decision in 1986 to remain outside NATO's integrated military structure, however, the issue of assignment of commands and missions in the Iberian Peninsula and adjacent sea areas became dormant.

Data as of January 1993