In 1861 he first took office, and was then a member of every Liberal Cabinet until his death. He was Secretary of State for War (1863-66) under Palmerston and Secretary of State for India in 1866 under Russell. In Gladstone's first administration he was Lord President of the Council 1868-73. During this period he acted as chairman of the joint commission for drawing up the Treaty of Washington with the United States. For this he was created Marquess of Ripon. In 1874 Ripon converted to Catholicism.
When Gladstone returned to power in 1880 he appointed Ripon Viceroy of India, and he held this office until 1884. In Gladstone's 1886 government he was First Lord of the Admiralty, and in that of 1892-95 he was Secretary of State for the Colonies. When the Liberals again returned to power in 1905 he took office, aged 78, as Lord Privy Seal and Leader of the House of Lords. He resigned in 1908, shortly before his death.
A devout Catholic, Ripon was generous in educational and charitable works. He was president of the Society of St Vincent de Paul from 1899 until his death and a great supporter of St. Joseph's Catholic Missionary Society. In 1851 he married his cousin Henrietta Vyner: they had two children.
{| border="2" align="center"
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|width="30%" align="center"|Preceded by:
New Creation
|width="40%" align="center"|Marquess of Ripon
|width="30%" align="center" rowspan="2"|Followed by:
Frederick Oliver Robinson
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|width="30%" align="center"|Preceded by:
Frederick John Robinson
|width="40%" align="center"|Earl of Ripon
|}