Uxbridge, a market town in the Uxbridge parliamentary division of Middlesex, England, 18 m. W. by N. of St Paul's Cathedral, London, on the river Colne, and on branches of the Great Western and Metropolitan railways. Pop. of urban district (1901), 8585. There are breweries, foundries and engineering works, and a considerable traffic is carried on by means of the Grand Junction Canal. The town, which is connected by electric tramway with Hammersmith, London, has extended considerably in modern times as a residential centre. The church of St Margaret is Perpendicular, and retains a fine font in that style, and several ancient monuments.
Uxbridge is an ancient borough, stated to have been one of those originated by Alfred the Great, but it is not mentioned in Domesday. Here negotiations were begun, on the 30th of January 1645, between the commissioners of Charles I. and the parliament, but were broken off on the 22nd of February. A part of the "Treaty House," in which they were carried on, remains. In 1647 the parliamentary forces had for some time their headquarters in the town. It remained a garrison town until 1689. It obtained the grant of a market from Henry II.