Lt Col William McCarthy O'Leary was the popular commanding officer of the 1st Battalion, The South Lancashire Regiment. He was killed on 27 February 1900 while leading his men at the Battle of Pieters Hill, which finally opened the road to the besieged town of Ladysmith during the South African (or Boer) War.
The Regiment drew many of its recruits from the then-South Lancashire town of Warrington, where Colonel O'Leary was very well known. When the town erected a memorial to the men of the Regiment who died during the war, it chose to feature a sculpture of Colonel O'Leary on campaign in South Africa. The statue, by sculptor Alfred Drury, was unveiled by General Sir Redvers Buller at a grand ceremony in 1907, and has remained in the same location ever since.