The museum is primarily concerned with history in South Wales focused on the ancient county of Monmouthshire.

There was historic ambiguity as to the status of the county of Monmouthshire.

It is within the historic county of Monmouthshire.

The name derives from the historic county of Monmouthshire of which it covers the eastern 60%.

The district was formed from areas in the administrative counties of Glamorgan and Monmouthshire.

The river forms the boundary between the historic counties of Glamorgan and Monmouthshire.

This article describes the geology of the historic county of Monmouthshire.

In the same year the parish of Fwthog was transferred to both the administrative and geographic county of Monmouthshire.

Gwent was an administrative county between 1974 and 1996, covering a similar but not identical area to the historic county of Monmouthshire.

Until 1938, the area was part of the civil parish of Rumney, in the former county of Monmouthshire.