William O'Neill, 1st Baron O'Neill

The eldest son of Reverend Edward Chichester, he was a member of the prominent Irish Chichester family headed by the Marquess of Donegall. He was the great-great-great-grandson of John Chichester, grandson of Edward Chichester, 1st Viscount Chichester, and younger brother of Arthur Chichester, 2nd Earl of Donegall. O'Neill was educated at Foyle College, Derry, Shrewsbury School and Trinity College, Dublin, and was ordained in 1837.

He was a prominent church organist and composer of church music, glees and songs.

When the Belfast Hospital for Sick Children was opened in 1878, Reverend O'Neill was appointed as the first president of the Medical Board. A marble dedication was installed in the hospitals surgical ward honouring him. This was a role he fulfilled with keen interest up until his death, at which time his son Robert Torrens took over the responsibility.[1]

In 1855 he succeeded to the substantial O'Neill estates on the death of his relative John O'Neill, 3rd Viscount O'Neill (on whose death the viscountcy became extinct) and assumed by Royal licence the surname of O'Neill in lieu of Chichester the same year. In 1868 the O'Neill title was revived when he was raised to the peerage as Baron O'Neill, of Shane's Castle in the County Antrim.[2]

Lord O'Neill married, firstly, Henrietta, daughter of Robert Torrens, judge of the Court of Common Pleas (Ireland), and his wife Anne in 1839. After her death in 1857 he married, secondly, Elizabeth Grace, daughter of the Venerable John Torrens, Archdeacon of Dublin, in 1858; she was Henrietta's first cousin. His third son from his first marriage, Robert Torrens O'Neill, represented Antrim Mid in Parliament for many years. He died in April 1883, aged 70, and was succeeded in the barony by his eldest son from his first marriage, Edward. Two of Lord O'Neill's descendants gained particular distinction. His grandson Robert William Hugh O'Neill was Speaker of the Northern Ireland House of Commons and created Baron Rathcavan in 1953 while his great-grandson Terence O'Neill was Prime Minister of Northern Ireland and given a life peerage as Baron O'Neill of the Maine in 1970. Elizabeth Grace, Lady O'Neill, died in 1905.

• Earl O'Neill
• Marquess of Donegall