He also developed a strong friendship with Richard Holt Hutton, a writer and theologian who influenced his views considerably.

On 15 September 1852, Richmond married Emily Elizabeth Atkinson, described by Joseph Hutton (father of Richmond's friend Richard Holt Hutton) as "a remarkable woman of singular intellectual power, moral earnestness and charming spontaneity of character".

[4] When Edward Stafford formed a government on 2 June 1856, Richmond accepted an invitation to become Colonial Secretary (forerunner to the modern Minister of Internal Affairs).

On 27 August 1858, he became New Zealand's first Minister for Native Affairs, but lost this post to Frederick Weld in late 1860.

Politically, Richmond aligned himself with the centralist faction, believing that the power of the provinces needed to be curtailed.

After the Stafford government fell, Richmond did not remain in Parliament for long, and he resigned on 20 January 1862.