The central legislative assembly of the Isle of Man, historically composed of the Lord Proprietor or Crown representative, the Governor and Council, and the Twenty-four Keys.

The 1792 constitutional inquiry described the more regular form of Manx legislation as resting on the concurrence of three branches: the Lord Proprietor, the Governor and Council, and the Keys. When the latter two assembled together they were called the Tynwald Court. Laws governing the Island were enacted through the joint concurrence of these branches.

The Council included senior lay and ecclesiastical officers. The 1792 report listed the Receiver-General, Comptroller, Clerk of the Rolls, Water-Bailiff, Attorney-General and Deemsters alongside the Bishop, Archdeacon, his Official and the two Vicars-General. Its function was to consider measures proposed by the Lord Proprietor or Governor and give assent or dissent.

The Keys formed the third branch. They were twenty-four principal commoners, described in the constitutional record as “the worthiest men in the land”. Their existence is documented in medieval records, including a declaration of law made to Sir John Stanley in 1422 and an act in which twenty-four Keys participated in 1417.

Tynwald was not simply an indoor legislative sitting. Its public ceremony at St John’s included the promulgation of laws. William Harrison’s nineteenth-century compilation preserved records of the Tynwald and St John’s chapels, including the order of procession for 5 July 1770 and drawings of Tynwald Hill made by Captain Grose in 1774.

Harrison also noted that other places had been associated with older Tynwald assemblies. He described an ancient Tynwald site near St Luke’s, Baldwin, which had been levelled by the time he visited it in the nineteenth century.