Manuel Monteiro de Castro is a Portuguese prelate of the Catholic Church who worked in the diplomatic service of the Holy See from 1967 to 2009, with the rank of archbishop and the title of nuncio from 1985. His assignments as nuncio included the Caribbean, South Africa, Central America, and Spain. He ended his career in senior positions in the Roman Curia from 2009 to 2013. He was made a cardinal in 2012.
He entered the diplomatic service of the Holy See in 1967. He was created Chaplain of His Holiness on 1 July 1968. He served as secretary of the nunciatures in Panama from 1967 to 1969, Guatemala from 1969 until 1972, Việt Nam and Cambodia from 1972 until 1975, Australia from 1975 to 1978, and Mexico from 1978 to June 1981. He was upgraded to prelate of honour of His Holiness on 1 July 1981. He then worked in the Second Section of the Secretariat of State from June to November 1981. He was counselor of the nunciature in Belgium from the end of 1981 until 1985. On 16 February 1985, Pope John Paul II appointed him titular archbishop of Beneventum; Apostolic Pro-Nuncio to the Bahamas, Barbados, Belize, Dominica, Grenada, Jamaica, Saint Lucia, and Trinidad and Tobago; and Apostolic Delegate to the other territories in the Antilles. His title change to Apostolic Nuncio to Granada on 30 April. He was consecrated a bishop by Cardinal Secretary of StateAgostino Casaroli..He became in addition Apostolic Nuncio to Antigua and Barbuda on 25 April 1987. He was named Apostolic Nuncio to both Honduras and El Salvador on 21 August 1990, but was replaced in Honduras by Luigi Conti on 12 April 1991. In 1998, he was appointed Apostolic Nuncio to South Africa, Namibia, and Swaziland on 2 February and Apostolic Nuncio to Lesotho on 7 March. On 1 March 2000, he was appointed Apostolic Nuncio to Spain and Andorra. He met with José Luis Rodríguez Zapatero to reduce tension between the Spanish government and the Church. Addressing a conference of Spanish bishops in 2004, he proposed they support the legal recognition of same-sex relationships called something other than "marriages". He said: "The new political situation in which we are living in Spain sets new challenges in the spreading of the gospel and we must meet those challenges in an appropriate manner.... There are other forms of cohabitation and it is good that they be recognised." On 7 December 2007, he was given the added role of Permanent Observer of the Holy See to the World Tourism Organization.