A £25,000 grant will enable visitors to Lanhydrock House to look at records charting the life of the stately home back to the 16th-century.
The grant, from the Cataloguing Grants Scheme, will enable the Cornwall Record Office o reveal the contents of an archive charting 400 years of life at the National Trust property which was owned by the Robartes family until 1953.
The records include papers from the English Civil War era, records relating to the rebuilding of the house after a fire in 1881 and more than 500 plans of properties and land.
The Cataloguing Grants Scheme is sponsored by a range of charitable foundations and administered by The National Archives.
It aims to help archives in the UK tackle their cataloguing backlogs.