The London Charterhouse is a historic complex of buildings in Smithfield, London, dating back to the 14th century. It occupies land to the north of Charterhouse Square, and lies within the London Borough of Islington.
The Charterhouse began as (and takes its name from) a Carthusian priory, founded in 1371 and dissolved in 1537. Substantial fragments remain from this monastic period, but the site was largely rebuilt after 1545 as a large courtyard house. Thus, today it "conveys a vivid impression of the type of large rambling 16th century mansion that once existed all round London".
The Charterhouse was further altered and extended after 1611, when it became an almshouse and school, endowed by Thomas Sutton. The almshouse (a home for gentlemen pensioners) still occupies the site today under the name The Charterhouse; the school moved out in 1872 to Godalming, Surrey, where it survives as Charterhouse School although its correct name does not include the word 'school'.
In 1348, Walter de Manny rented 13-acre (0.05 km2) of land in Spital Croft, north of Long Lane, from the Master and Brethren of St. Bartholomew's Hospital for a graveyard and plague pit for victims of the Black Death. A chapel and hermitage were constructed, renamed New Church Haw; but in 1371, this land was granted for the foundation of the London Charterhouse, a Carthusian monastery.
The twenty-five monks each had their own small building and garden. Thomas More came to the monastery for spiritual recuperation. The name is derived as an Anglicisation of La Grande Chartreuse, whose order founded the monastery.
The monastery was closed in 1537, in the Dissolution of the Monasteries in the English Reformation. As it resisted dissolution the monastery was treated harshly: the Prior, John Houghton was hanged, drawn and quartered at Tyburn and ten monks were taken to the nearby Newgate Prison; nine of these men starved to death and the tenth was executed three years later at Tower Hill. They constitute the group known as the Carthusian Martyrs.