Glamorganshire was a parliamentary constituency in Wales, returning two Members of Parliament (MPs) to the English and later British House of Commons. The Redistribution of Seats Act 1885 divided it into five new constituencies: East Glamorganshire, South Glamorganshire, Mid Glamorganshire, Gower and Rhondda.

This constituency comprised the whole of Glamorganshire.

For most of its history, the county constituency was represented by landowners from a small number of aristocratic families and this pattern continued until the nineteenth century. Following the Great Reform Act of 1832 a second county seat was created.

By the 1850s it had become virtually impossible for a Tory candidate to be elected as a county member since the industrial and urban vote could be rallied against him. This was proved in 1857 when Nash Vaughan Edwards-Vaughan failed in his attempt to dislodge one of the sitting members.^[1] Thereafter, until redistribution in 1885 led to the abolition of the constituency, the representation was shared by C.R.M. Talbot and Hussey Vivian. In line with Liberal party policy in two-member constituencies to run candidates from both wings of the party, the Whig aristocrat Talbot collaborated well with the more Radical Vivian.^[1]