Cabo Delgado is the northernmost province of Mozambique. It has an area of 82,625 km2 (31,902 sq mi) and a population of 2,320,261 (2017). As well as bordering Mtwara Region in the neighboring country of Tanzania, it borders the provinces of Nampula and Niassa. The region is an ethnic stronghold of the Makonde tribe, with the Makua and Mwani as leading ethnic minorities.

Operation Gordian Knot was the largest and most expensive Portuguese military campaign in the Portuguese overseas province of Mozambique, East Africa. The operation was carried out in 1970, during the Portuguese Colonial War (1961–1974). The objectives of the campaign were to close down the Mozambique Liberation Front (FRELIMO)'s infiltration routes across the Tanzanian border and to destroy permanent FRELIMO bases inside the liberated zones in Northern Mozambique. Gordian Knot was a seven-month long campaign ultimately employing thirty-five thousand men, and was almost successful since it destroyed most guerrilla camps located inside FRELIMO's liberated zones and captured large numbers of rebels and armaments, forcing FRELIMO to retreat from their bases and outposts in the provinces. The operation ultimately failed when FRELIMO forces regrouped and thrust further south into the province of Tete, opening a new front and overstretching the Portuguese Army. The failure of Gordian Knot helped fuel the discontent that led to the Carnation Revolution in April 1974.