In 1854, the Society re-established its missionary base at
Keppel Island in the Falkland Islands; Stirling became secretary of the mission in England. In 1861 he went to Keppel Island as the mission superintendent. From there, he re-established contacts with the Yaghan of Tierra del Fuego. In January 1869 he served as a lone missionary at
Ushuaia in Tierra del Fuego.[4]
Whilst serving at Ushuaia as "God's Lonely Sentinel", as Stirling called himself, he was summoned to
London to be consecrated on 21 December 1869 in
Westminster Abbey as "
Bishop of the Falkland Islands." It was contemporary practice to name overseas
bishoprics after one of
Her Majesty's possessions. Seven consular
chaplaincies in
South America and several private company chaplains were placed under Stirling's
jurisdiction. He spent his first few years establishing his authority over recalcitrant clergy and congregations. They resented this Episcopal "upstart" and thought they still owed allegiance to the
Bishop of London, previously responsible for the supervision of overseas Colonial and Consular Chaplaincies.
The Anglican mission at Ushuaia was expanded by
Thomas Bridges and George Lewis, who lived there with their families starting in 1871. Later relocated within the Tierra del Fuego archipelago, the mission was continued by other ministers until 1916.
On 14 January 1872, Bishop Stirling was assigned his "Throne and Episcopal Chair" by the Colonial Chaplain, the Reverend
Charles Bull. His enthronement was to take place in the Exchange Building in
Port Stanley; however, Stirling refused to be enthroned in "half a commercial building" because it was not a
cathedral. After a wall of the Exchange Building was destroyed in 1886, the present
Stanley Cathedral was built, and consecrated in 1892.
Stirling resigned from the Falklands diocese in 1900 to become a Canon and Assistant Bishop at
Wells Cathedral in England. He remained there for twenty years until his retirement at the age of 91.