[2] He served under David Lloyd George as Postmaster General from 1916 to 1921 and was sworn of the Privy Council in 1916.

[3] In 1921 he was raised to the peerage as Baron Illingworth, of Denton in the West Riding of the County of York.

[5] Lord Illingworth married firstly Annie Elizabeth, daughter of Isaac Holden Crothers, in 1895.

He married secondly Margaret Mary Clare, daughter of William Basil Wilberforce, in 1931.

His second wife died in 1986, having become before her death the victim of a massive defrauding of her estate by her niece who had been investigated over the murder of Simon Dale, the latter's ex-husband.