A market-town and municipal borough in the Watford parliamentary division of Hertfordshire, England, 25 m. N.W. from London, with a station on a branch of the Midland railway from Harpenden, and near Boxmoor station on the London and North Western main line. Pop. (1891) 9678; (1901) 11,264. It is pleasantly situated in the steepsided valley of the river Gade, immediately above its junction with the Bulbourne, near the Grand Junction canal. The church of St Mary is a very fine Norman building with Decorated additions. Industries include the manufacture of paper, iron founding, brewing and tanning. Boxmoor, within the parish, is a considerable township of modern growth. Hemel Hempstead is governed by a mayor, 6 aldermen and 18 councillors. Area, 7184 acres.
Settlements in the neighbourhood of Hemel Hempstead (Hamalamstede, Hemel Hampsted ) date from pre-Roman times, and a Roman villa has been discovered at Boxmoor. The manor, royal demesne in 1086, was granted by Edmund Plantagenet in 1285 to the house of Ashridge, and the town developed under monastic protection. In 1539 a charter incorporated the bailiff and inhabitants. A mayor, aldermen and councillors received governing power by a charter of 1898. The town has never had parliamentary representation. A market on Thursday and a fair on the feast of Corpus Christi were conferred in 1 539. A statute fair, for long a hiring fair, originated in 1803.