The Rt Rev William Walmsley Sedgwick (1858–1948) was the 5th Anglican Bishop of Waiapu whose Episcopate spanned a 15-year period during the first half of the 20th century.
Born at Freemantle in Southampton, William Sedgwick was educated at Christ's College, Cambridge and ordained in 1882. He embarked on his career with a curacy at St. John The Baptist, Wateringbury and a short spell as a Naval Chaplain. Later he held incumbencies in Hockley Heath, Vryburg and Bedford, Eastern Cape. From 1897 to 1900 he was Chaplain to the Earl of Home and between 1900 and 1914 he worked in New Zealand, eventually becoming Bishop of Waiapu. His last post was as Vicar of Detling.