[4] In 1885 he and his brother, Arthur Twistleton Polhill, became affiliated with the China Inland Mission (CIM) as part of the Cambridge Seven missionary band.
The Polhills studied local language in Hanzhong, southwest Shaanxi, then in 1887 moved into the neighbouring province Sichuan (formerly spelt Szechwan).
Cecil Polhill was at first based at the provincial capital, Chengdu, and the eastern Sichuanese city Chongqing, but he felt drawn towards the people of Tibet.
In 1894, at Annie Royle Taylor's suggestion, Polhill assumed the leadership of her Tibetan Pioneer Mission, whose members included Edvard Amundsen and Theo Sørensen.
[17] In 1925 the Executive Council of the PMU voted to merge with the British Assemblies of God, and so Polhill, an Anglican, resigned aged 65.