William was born at The Reddings, Cheltenham, Gloucestershire. His army record recorded this as 'Reading, Berkshire'. He was the son of Mary Jane Yeates who married Edwin Wales Chegwin in 1892. William's army record refers to an 'Aunt Mary' in Aberdare. Aunt Mary was Mary Rees who was married to Benjamin John Organ (known as John). John was William's 1st cousin 1x removed through William's maternal grandmother, Elizabeth Welch. He enlisted in Aberdare.