The formation of Mamut into a parish owed its beginning to the ministry of Peter Howes when he was transferred to Miri in 1965 to assume his Archdeacon responsibility. The Iban inhabitants along the Sibuti and Niah river had earlier migrated from Undup in the Second Division, under the leadership of Penghulu Barat in the 1930s. Some of the migrants claimed to be Christians from their Undup days. When Brian Taylor visited Mamut, the people claimed that they had never been visited by a priest in 35 years!
It was to check Taylor’s story that Peter Howes made his first visit to Mamut. He took a boat from Miri, and via Bekenu, made his journey up the Sibuti. His first stop was at Pidek. Further up is Mamut, the house of Penghulu Mancha. And still further is Kelitang. In all those places, Howes found some Anglicans among the government servants.
In 1967, a chapel (St. Aidan) and a priest ‘langkau’ were built by the Christian population of Kelitang, hoping perhaps to pre-empt Mamut as a possible mission centre. Howes stayed for a while at Kelitang and prepared the folks there for baptism and confirmation. The visit to the Sibuti region was made easier in 1968, when a trunk road was built from Miri to Batu Niah. In 1968, Howes moved from Miri to Mamut, where a church (St. Boniface) was built in 1969. From Mamut, Howes continued to minister to the Christians at kelitang. Pidek was at last opened to the Faith and Howes prepared the catechumens for baptism and confirmation. Later, the folks at Batu Niah also indicated a desire to embrace Christianity and Howes obliged. Malang was also opened to the Niah and in 1969, Bishop Basil visited the place to confirm the baptised converts.
Howes left for Kuching in December 1969. Meanwhile, Ngitar Mai took charge of Miri and the Subis District. In early 1970, Edmund Paleng arrived and became the priest in charge of the Subis District.