The pre-history of Hillfields from the 12th - 18th Century 

Harnall is the former name of the district in Holy Trinity Parish, part of which later became known as Hillfields. The northwest of the district is crossed by the old Leicester Causeway and Stoney Stanton Road, a former turnpike. A road, said in the 12th century to lead "through the middle of Harnall along the country of Stoke" and in the 15th Century to run "through the middle of Harnall towards Wyken" was probably Harnall Lane. The medieval Sewal Pavement, leading towards Bulkington, may have been an earlier form of Leicester Causeway. 

The land rises from the River Sherbourne towards Great Heath. It was crossed by two streams, the courses of which are now partly lost. In the west was Springfield Brook, the medieval Endemere, later known as the Harnall or Swanswell Brook, which ran south across Foleshill Road and by Swanswell Pool above the mill there. In the east the Spitalmoor Brook ran southwest to meet Springfield Brook, which in turn ran into the Sherbourne.

Harnall was first mentioned in Coombe Abbey Charter as being in the bounds of the Prior's Half of Coventry in the 12th Century. The boundary of the half followed the Endemere and the road "through the middle of Harnall" Most of Harnall was in the ancient Hasilwood with open field cultivation, used to feed stock for the Coventry market. 

Harnall was one of the estates of Roger de Montalt in 1279 when the property consisted of six cottages, and a number of crofts and other pieces of land. The tenurial arrangements were complex. Five men  held of Roger, each had one or more tenants, some of whom had sub tenants. 

Coventry Priory held land in Harnall, then called a manor, by 1221. It had acquired other land in 1223, 1232 and 1369. By 1410 - 11 the priory had a considerable estate there. The priory's demesne estate was among lands granted in 1542 to the Corporation, and in 1551 the Prior's Orchard with two pools (Swans Pool and New Pool), Harnall Field and other land were included in the endowment of Sir Thomas White's Charity. 

Prior's Orchard Mill (New Mill, Swanswell Pool Mill, reference to tenters suggests a fulling mill) stood at the point where the western branch of Springfield Brook left Swanswell Pool. In 1632 it became absorbed into the Swanswell Waterworks. 

In 1538 a well and conduit existed in Harnall Field. In 1632, a more important undertaking was accomplished for the distribution of water. In this year water works at Swanswell were constructed for the supply of water to the city, by Bartholomew Bewley, a plumber, and Thomas Surgeon, a mason. The water was conducted from a spring in a field near Swanswell Pool, by means of lead pipes, through the Priory Orchard, under the city wall, through the Pool Yard, or Pool Meadow, then up the Priory into the town. The reservoir was attached to premises in "Cuckoo Lane". The engine for forcing the water through the mains, worked by waterpower, was placed in a building opposite the Swanswell Pool.

Development of the New Town began in 1828 but it was separated from the city by the River Sherbourne which was obstructed by two mills which caused it to flood. These mill could not be pulled down until an Act of Parliament was obtained in 1844. When this was done, the Ford Street and Lower Ford Street area could be developed and the old city joined to the new town.

More about the history of Swanswell pool

A description of Hillfields before it was developed