Ernest William Barnes FRS[1] (1 April 1874 – 29 November 1953) was a British mathematician and scientist who later became a liberal theologian and bishop.

In 1883 Barnes' father was appointed Inspector of Schools in Birmingham, a position that he occupied throughout the rest of his working life.

[8] In the same year he became a lecturer in mathematics, Barnes was made deacon by the Bishop of London and from 1906 to 1908 was Junior Dean of Trinity.

This was followed in 1918 by a canonry of Westminster Abbey and finally, in 1924, by consecration to the Bishopric of Birmingham, an office he held until April 1953, when he had to retire on account of ill-health.

[11] Undaunted by this set-back, Barnes returned to his accusations on the cement ring in a speech he delivered in the House of Lords the following year.

Several of these eugenic-themed lectures gained significant newspaper coverage in The Times and The Manchester Guardian, sparking a fervent public debate in which inevitable – if not entirely justifiable – parallels were drawn between Barnes' arguments and Nazi ideology.

[15] Together they had two sons: John was a diplomat, who served as ambassador to Israel and the Netherlands; and William, a public servant and philanthropist.