Lamport Hall was the home of the Isham family from 1560 to 1976.
The first house was built by John Isham, a younger son from a Northamptonshire family, who made his fortune as a merchant.
In 1655 his great-grandson, Justinian, commissioned John Webb, a pupil of Inigo Jones, to add an extension to the parlour-end of the Tudor house.
The five bay section, an example of Renaissance-inspired classicism, is now at the centre of the garden front.
Justinian's son, Thomas, went on a Grand Tour in 1676 and many of the paintings he purchased during this time can still be seen at Lamport Hall.
In 1732-40 Francis Smith of Warwick was employed to add wings on either side of Webb's building.
The remnants of the old building were swept away in 1819-21 when a new dining room was built on the site of the Tudor hall to designs of Henry Hakewill. In 1861 the entrance front was remodelled by William Burn.
The last member of the family to occupy the house was Sir Gyles Isham, an actor and historian.
Sir Gyles left the house to the charitable Lamport Hall Trust.
The proportions of Lamport Hall are determined by Webb's building of 1655 which has details borrowed from Inigo Jones's Banqueting House in London including rusticated stonework, semicircular and triangular pediments alternating over the windows and a balustrade at roof level. The pediment and pitched roof were added later.
The rooms have furniture and pictures, including art brought back from Sir Thomas Isham's Grand Tour.
The Library contains books from the 16th century, a Bible that once belonged to Charles I and what is said to be the oldest garden gnome in England, brought to the house by Sir Charles Isham in the mid-19th century.
The Oak Room next door has paintings by Salvator Rosa. The Staircase Hall ceiling dates from 1740 and armorial glass was brought to Lamport Hall from the demolished Pytchley Hall, another of the Isham family's houses.
The entrance hall, known as the High Room, is the finest room and takes up most of Webb's building.
The elaborate chimneypiece carved by Caius Gabriel Cibber still remains. On the walls are copies of the famous Stuart portraits, acquired by Sir Justinian Isham, a staunch Royalist, who refused to take them down during the Interregnum. The panelling was added in 1686 and the plasterwork on the ceiling was created by John Woolston of Northampton in 1738 - 40.
The Cabinet Room in the other Smith Wing contains some of the best paintings in the house, including works by Van Dyck and Sebastiano Ricci. The room is named after the four splendid late-17th century Flemish and Neapolitan cabinets acquired in the 1770's.
The first-floor rooms now open to the public contain pictures and furniture and a children's nursery.
There are also exhibitions including a photographic record of Sir Gyles, who was a Hollywood actor.
Lamport Hall is set in gardens and surrounded by a spacious park.
The gardens were laid out in 1655 but their character owes much to Sir Charles Isham, the eccentric 10th Baronet.
In the mid-19th century he created the Italian Garden and the Rockery, where he placed the first garden gnomes to be seen in England.