From the Wikipedia page 
Edmonton was an ancient hundred in the north of the county of Middlesex, England. Its former area has been mostly absorbed by the growth of London and it now corresponds to the London Borough of Enfield and parts of the London Borough of Barnet and London Borough of Haringey in Greater London and the Hertsmere district in Hertfordshire.
The hundred was listed in the Domesday Book in 1086, after which there were only very minor boundary changes. It was sometimes known as the Half Hundred of Mimms.
It contained the parishes and settlements of Edmonton, Enfield, Monken Hadley, South Mimms and Tottenham. It bordered Ossulstone hundred to the south west, and had a boundary with Essex to the east. In the north west it formed a protrusion into Hertfordshire (containing South Mimms and Monken Hadely) and was bounded by it to the north, west and south.
The Hundred Moot appears to have originally been held near Potters Bar. By the seventeenth century the "mote plane" was in an open area of Enfield Chase. The court for the hundred eventually moved to a public house in Enfield prior to its abolition in 1846.
The hundreds of England declined in administrative use because of the rise of various ad-hoc boards. By 1894 they were effectively replaced by a system of uniform local government districts, which were consolidated over time and finally replaced in 1965/1974 by the London boroughs and non-metropolitan districts which are still in use today.