Question: Manuel Quintas de Almeida, was a lieutenant in the military of São Tomé and Príncipe, a Portuguese-speaking island nation, in which location?

Context paragraphs:
Central Bank of São Tomé and Príncipe: The Central Bank of São Tomé and Príncipe (Portuguese: "Banco Central de São Tomé e Príncipe" or BCSTP) is the central bank of São Tomé and Príncipe, a Portuguese-speaking island nation off the western equatorial coast of Central Africa.

Politics of São Tomé and Príncipe: The politics of São Tomé and Príncipe takes place in a framework of a unitary semi-presidential representative democratic republic, whereby the President of São Tomé and Príncipe is head of state and the Prime Minister of São Tomé and Príncipe is head of government, and of a multi-party system.  Executive power is exercised by the President and the Government.  Legislative power is vested in both the government and the National Assembly.  The Judiciary is independent of the executive and the legislature.  São Tomé has functioned under a multiparty system since 1990.  Following the promulgation of a new constitution in 1990, São Tomé and Príncipe held multiparty elections for the first time since independence.  Shortly after the constitution took effect, the National Assembly formally legalized opposition parties.  Independent candidates also were permitted to participate in the January 1991 legislative elections.

List of companies of São Tomé and Príncipe: São Tomé and Príncipe is a Portuguese-speaking island nation in the Gulf of Guinea, off the western equatorial coast of Central Africa.  It consists of two archipelagos around the two main islands: São Tomé and Príncipe, located about 140 km apart and about 250 and , respectively, off the northwestern coast of Gabon.

Manuel Quintas de Almeida: Manuel Quintas de Almeida (1957 – 26 December 2006) was a lieutenant in the military of São Tomé and Príncipe.

Água Grande District: Água Grande is a district of São Tomé Province.  Its capital, São Tomé, is also the provincial capital of São Tomé, and national capital of the equatorial Atlantic island nation of the Democratic Republic of São Tomé and Príncipe.  Covering only 17 km2 , it is the smallest of the nation's seven districts in terms of area, but the largest in population with 73,091 residents (2012).  The entire district forms a part of the São Tomé City Metropolitan Area.

São Tomé and Príncipe: São Tomé and Príncipe ( ; ] ), officially the Democratic Republic of São Tomé and Príncipe, is a Portuguese-speaking island nation in the Gulf of Guinea, off the western equatorial coast of Central Africa.  It consists of two archipelagos around the two main islands: São Tomé and Príncipe, located about 140 km apart and about 250 and , respectively, off the northwestern coast of Gabon.

Military of São Tomé and Príncipe: The Armed Forces of São Tomé e Príncipe (FASTP, "Forças Armadas de São Tomé e Príncipe" in Portuguese) are the armed forces of the island nation of São Tomé and Príncipe, off the coast of West Africa.  The islands' military consists of a small land and naval contingent, with a limited budget.  Sitting adjacent to strategically important sea lane of communication in the Gulf of Guinea, due to recent concerns about regional security issues including security for oil tankers transiting the area, the US military and other foreign navies have increased their engagement with the FASTP, providing the country with assistance in the form of construction projects and training missions, as well as integration into international information and intelligence sharing programs.

Cuisine of São Tomé and Príncipe: Santomean cuisine comprises the cuisine, dishes and foods of São Tomé and Príncipe, a Portuguese-speaking island nation in the Gulf of Guinea, off the western equatorial coast of Central Africa.  The country consists of two archipelagos around the two main islands: São Tomé and Príncipe, located about 140 km apart and about 250 and , respectively, off the northwestern coast of Gabon.

China–São Tomé and Príncipe relations: In 1997, São Tomé and Príncipe recognized the Republic of China as the sole legitimate government of China.  However, in 2013, the People's Republic of China established a trade office in São Tomé and Príncipe, and the next year President Manuel Pinto da Costa visited China in a private capacity.  Bilateral relations between São Tomé and Príncipe and the Republic of China were terminated on 21 December 2016.  Hereafter, São Tomé and Príncipe established diplomatic relations with the People's Republic of China, and in April 2017, a People's Republic of China embassy was opened in the capital of São Tomé and Príncipe.

Air São Tomé and Príncipe: Air São Tomé and Príncipe (Linhas Aéreas de São Tomé e Príncipe, Lda) was an airline based in São Tomé, São Tomé and Príncipe.  It operated scheduled services within the islands and to neighbouring Gabon.  Its main base was São Tomé International Airport.  It lost its only aircraft in an accident in 2006.

Supporting paragraphs: Manuel Quintas de Almeida São Tomé and Príncipe
Answer: Gulf of Guinea