In 1574 the then lord of the borough, Bernard Brocas, granted a 2000-year lease of the borough to six trustees to hold on behalf of the corporation in return for an annual rent of 40s. The lordship was purchased by Sir Thomas Temple in 1604. Payment of this rent to his successors was discontinued in the 19th century. During the period 1641-1889 the Temple family and their successors the Grenvilles, who later became Marquesses and Dukes of Buckingham and Chandos, also held the post of steward (apart from a brief period in the reign of James II) and they dominated the borough and the election of its MPs until the Municipal Corporations Act 1835. In 1684 the borough received a new charter from Charles II, by which the bailiff and principal burgesses were given the new titles of "Mayor and Aldermen". A dispute with James II over the appointment of a new steward, when the king unsuccessfully tried to secure the election of Lord Chancellor George Jeffreys, led to the dismissal of three mayors by the king in 1687-88. In 1688 James restored the charter of Mary I and the older titles of "Bailiff and Principal Burgess" were resumed by the mayor and aldermen. In the 18th century the earliest known references to the offices of recorder and town clerk, not mentioned in the charter, appear. The administration of the borough was reformed as a result of the Municipal Corporations Act 1835, when it became a municipal borough, and was placed in the hands of a mayor, four aldermen and six councillors. The reformed borough was granted its own Court of Quarter Sessions in 1836 and a small borough police force, Buckingham Borough Police, was formed. The grant of quarter sessions was revoked in 1890 when the office of recorder was consequently abolished and the town clerk lost his title of clerk of the peace. In 1892 the police force was amalgamated with Buckinghamshire Constabulary. The borough council was abolished in 1974 when, as a result of local government re-organization, the borough was merged with Buckingham Rural District and Wing Rural District to create the district of Aylesbury Vale. The Buckingham Three Weeks Court, which had not sat since 1820, was also formally abolished at that time. The boundaries of the borough and parish of Buckingham were co-extensive. As set out in the charter of Mary I, they extended from Dudley bridge in the west to Thornborough bridge in the east and from Chackmore brook in the north to Padbury Mill bridge in the south.