The Diocese of Masasi is one of the historical products of the pioneer appeals for mission work made by Bishop Selwyn in Great St Mary’s, Cambridge in November 1853, resulting in Charles Mackenzie offering himself for the African Mission.   He later became the first Bishop of “the mission to the tribes dwelling in the neighbourhood of the Lake Nyasa and the river Shire”.

In 1857 David Livingstone, a Scottish Presbyterian who worked for the London Missionary Society as an explorer in east and central Africa made an appeal to the Church of England, represented by her two oldest Universities of Oxford and Cambridge.   His appeal led to the establishment of the Oxford and Cambridge Mission to Central Africa, which later became the Universities Mission to Central Africa (UMCA).

As a result of the establishment of the UMCA the missionaries came to Masasi in obedience to the Great Mission and in the power of the Holy Spirit to make disciples of Jesus Christ.   As a result, the Diocese of Masasi was developed and the first Bishop, Bishop William Lucas, was consecrated on 29 September 1926 and was enthroned at Masasi Cathedral on 2 April 1927.

In 1945 Bishop Leslie Stradling succeeded Bishop William Lucas as the second Bishop of Masasi; he was succeeded in 1952 by Bishop Mark Way and in 1960 Bishop Trevor Huddleston became the fourth Bishop of the Diocese.

In 1968 Bishop Hilary Chisonga succeeded Bishop Trevor as the first African Bishop of the Diocese; he was succeeded by Bishop Richard Norgate and in 1992 Bishop Christopher Sadiki became the second African Bishop of the Diocese.

The present Bishop, the Rt Reverend Patrick Mwachiko is the eighth Bishop of the Diocese and he was consecrated and enthroned in Masasi Cathedral on 8 September 1996.

The Diocese of Masasi is located in the southern part of the Republic of Tanzania, bordered by Mozambique to the south, the Indian Ocean to the east and the Selous Game Reserve to the north and west. It covers about 105,000 sq kms (Mtwara and Lindi regions and Tunduru district in Ruvuma region), and apart from the coastal strip, much of the area consists of tropical forests and tropical grassland. The area is relatively flat and interrupted by small, widely scattered hills.

There are two very distinct seasons: the rainy season from November to April/May and a dry spell from June to November. Rainfall ranges between 500 to 800 mm per year.

The population of 3,268,408 persons (2005 census) is largely composed of four major tribes - the Wayao, Wamakonde, Wamakua and Wamwera and approximately 24% of the people are Anglicans.  The people are typically indigenous to the area and are subsistence farmers, surviving on small-scale farming and mainly using hand hoes, axes and machetes. However, some of the people who live along the shores of the Indian Ocean and the Ruvuma River practice fishing, using traditional canoes and wooden boats. The people live in Ujamaa (communal or family hood) villages in which every family has sufficient land to live on and farm.

The area is one of the poorest parts of Tanzania with an average per capita yearly income of Tshs 260,840/- (£105) and a poverty level of 37.98%. The economy is heavily dependent on agriculture, which accounts for half of the gross domestic product, provides 85% of exports and employs 80% of the work force. Cultivation is generally done using traditional tools and it is carried out on small acreages of between one to three acres. Food crops are mostly maize, rice, millet, oil seeds and cassava as food crops but cashew nuts and coconuts are also grown as cash crops. The topography and climatic conditions, however, limit the cultivation of crops to only 4% of the land area and, as a result, industry is mainly limited to processing agricultural products and light consumer goods.