[4][5] In the nineteenth century, although students from all religious denominations were legally entitled to attend universities, they were forbidden by statute from taking degrees unless they conformed to the Church of England.

The Prime Minister who enacted these reforms, William Ewart Gladstone, encouraged the creation of a Nonconformist college at Oxford.

The Victorian buildings, designed by Basil Champneys on a site bought from Merton College, were formally opened in October 1889.

Until 2007 Mansfield trained United Reformed Church (URC) ordinands, who became fully matriculated members of the university and received degrees.

The college chapel is unconsecrated, and contains stained glass windows and statues depicting leading figures from Nonconformist movements, including Cromwell, Sir Henry Vane and William Penn.

Over the years attendance at chapel services has declined and the make-up of the general student body no longer reflects the Nonconformist religious origins of the college.

However, early outlines of schematics for the college show an enclosed second quadrangle behind the main building, with the front tower serving as a gatehouse into this area.

[12] The latest addition to the college's facilities, the Hands Building, was designed by Rick Mather Architects and uses renewable energy sources.

[13] It incorporates 74 en-suite study bedrooms, seminar rooms and a 160-seat auditorium that will be used for lectures, as a cinema, moot court and performing arts space.

[20] In 2011, Mansfield College adopted two distinct pre-supper graces, one religious and one non-religious, in an effort to be inclusive to persons of different faiths, or none.

[21] Prior to 2011, the college used the following, specifically Christian grace, adopted in 1953:[22] Omnipotens Deus, clementissime Pater, omnis boni fons, in donis tuis gaudentes nomen tuum magnificamus, per Jesum Christum Dominum nostrum.

Honorary fellows of the college include Jimmy Carter, 39th President of the US; Shami Chakrabarti, former director of the civil rights group Liberty and chancellor of Oxford Brookes University; journalist and economist Will Hutton; politician Paddy Ashdown; actress Dame Maggie Smith; US senator Hillary Clinton; and barrister Helena Kennedy, Baroness Kennedy of The Shaws.