Picture appears to be taken in front of the main church entry door. The group likely performed a "ring" of the bells to celebrate lifting of the siege in 1900.
The Siege of Mafeking was a 217-day siege battle for the town of Mafeking (now called Mafikeng) in South Africa during the Second Boer War from October 1899 to May 1900. The siege turned the British commander, Colonel Robert Baden-Powell, into a national hero. The Relief of Mafeking (the lifting of the siege), while of little military significance, was a morale boost for the struggling British.