Oliver Sheppard was born in Cookstown, Co Tyrone. After his birth the family moved to Dublin, and he studied at the Metropolitan School of Art. He won a scholarship to the South Kensington Art School, where he studied from 1889 to 1891 before spending a year in Paris. He taught in Leicester and Nottingham.
When he returned to Dublin in 1902 he was appointed instructor in modelling at the Metropolitan School of Art. He was Professor of Sculpture to the Royal Hibernian Academy and exhibited there and at the Royal Academy. He represented Ireland in exhibitions in Europe, and in 1905 founded the Royal Society of British Sculptors. His work ‘The Death of Cuchulain’ was chosen as a memorial to the 1916 Rising and is in the GPO in Dublin.