Their ancestor was Richard Ladde, grandfather of the Lord Chief JusticeSir Edward, who changed his name to Montagu around 1447. His descendants claimed a connection with the older house of Montagu or Montacute, Barons Montagu or Montacute and Earls of Salisbury, but there is no sound evidence that the two families were related. A case has been made out for the possibility that the Ladde alias came from a division among coheirs about 1420 of the remaining small inheritance of a line of Montagus at Spratton and Little Creton, also in Northamptonshire. The judge Sir Edward Montagu's grandson, Edward Montagu, was raised to the peerage as 1st Baron Montagu of Boughton. He is the ancestor of the Dukes of Montagu. His brother, Sir Henry Montagu, who served as Lord Chief Justice as well as Lord High Treasurer and Lord Privy Seal, was in 1620 raised to the Peerage of England as Viscount Mandeville, with the additional title Baron Montagu of Kimbolton, of Kimbolton in the County of Huntingdon. In 1626, he was made Earl of Manchester, of Manchester in the County of Lancaster. It is said, erroneously, that the title referred not to the city of Manchester, but to Godmanchester in Huntingdonshire. The word "God" was deliberately excluded from the title, as Henry thought it would be blasphemous for him to be known as "Lord Godmanchester". His son, the 2nd Earl, was a prominent Parliamentary General during the Civil War, but later supported the restoration of Charles II. His son, the 3rd Earl, represented Huntingdonshire in the House of Commons. His son was the 4th Earl, who in 1719 was created Duke of Manchester.
The principal estate of the Dukes of Manchester was Kimbolton Castle. It was sold, together with 50 acres of parkland, by the 10th Duke in 1951, and is now a private school. A remaining 3,250 acres of the estate were sold by his eldest son and heir in 1975. The other family seat was Tandragee Castle, in County Armagh, Northern Ireland. It was sold in 1955, and the remaining estate in 1975, and is now the headquarters of Tayto Ltd.
Arms
The arms of the Duke of Manchester have the following blazon: Quarterly, 1st & 4th: Argent, 3 fusils conjoined in fess gules; 2nd & 3rd: Or an eagle displayed vert beaked and membered gules. The fusils or diamond shapes in the Montagu arms were originally intended to represent a range of mountains, as the name comes from the old Frenchmont agu meaning "pointed hill". The arms represent a claim to be a cadet of the medieval Montagu family, earls of Salisbury, for which there is no proof.
Titles and styles
The Duke of Manchester holds the subsidiary titles Earl of Manchester, Viscount Mandeville, and Baron Montagu of Kimbolton. The Duke of Manchester is styled Your Grace or His Grace, alternatively Sir. The heir apparent to the Dukedom takes the courtesy titleViscount Mandeville, and the heir apparent's heir apparent, when such exists, is styled Lord Kimbolton.
Burial place
Many members of the Montagu family are buried at St Andrew's Church, Kimbolton, Cambridgeshire. Several Montagu monuments still exist in the South Chapel, while the Montagu vault is located beneath the North Chapel. The 12th Duke of Manchester was cremated at Bedford Crematorium in 2002.