Situated adjacent to Ermin Way, the Roman road connecting present-day Gloucester and Silchester, Siddington has multiple examples of Romano-British settlements.

During the Industrial Revolution, the Thames and Severn Canal was built through the parish, followed by the Cirencester branch line and the Swindon and Cheltenham Extension Railway in the 1840s and 1880s respectively.

[2] Ermin Way, the Roman road connecting Glevum (Gloucester) to Calleva Atrebatum (Silchester) via Corinium (Cirencester) forms part of the parish's north-eastern border.

[4] Siddington was recorded in the Domesday Book of 1086 as comprising 46 households, putting it in the top fifth of English settlements as regards population.

Landowners of Siddington following the Norman Conquest included Godric, Leofwin, and Emma (wife of Walter de Lacy).

At this time, Siddington was recorded as having landowners including Roger of Lacy, Hascoit Musard, Humphrey the Chamberlain, and William fitzBaderon.

[5][7] The survey showed that Siddington had at least 17 villagers, 18 smallholders, 13 slaves, and 2 priests, as well as a mill and 20 acres (8.1 ha) of meadowland.

[a][9] Immediately west of the top lock was a wharf and basin where a short canal arm led north into Cirencester.

The line did not serve Siddington until 1960, however, when Park Leaze Halt opened across the Kemble parish border.

[14] John Marius Wilson's Imperial Gazetteer of England and Wales (1870–72) described how Siddington parish covered 1,950 acres (790 ha), had a property value of £2,777 (equivalent to £313,186 in 2023), and a population of 474 within 110 households.

[16] John George Bartholomew's Gazetteer of the British Isles, published in 1887, noted the size of the parish as 2,317 acres (938 ha) and showed that the population had risen to 481.

[20] The railways were removed in the 1960s; while the decline and closure of the MSWJR preceded it,[21] the Cirencester Branch was a casualty of the Beeching Axe of the early 1960s.

[25] Since 2024 it has been a part of South Cotswolds constituency[26] represented in Parliament by Dr Roz Savage of the Liberal Democrats.

[1] Ethnically, Siddington is 96.3% White British, with a majority of respondents reporting their national identity as English.

[1] Early industries in Siddington include brickmaking; the presence of clay pits and quarries is marked on Ordnance Survey maps of c. 1888–1913.

[48][49] A windmill was built in the late 18th century to grind corn; the Mills Archive does not note its operational dates[50] but its Grade II listing shows that by the 1980s it was "semi-derelict" and had become known as the Round House.

[52] The number of VAT registered companies per 10,000 working age population is above both the national average and that of Gloucestershire as a whole.

[51] Scheduled monuments in the parish include the tithe barn at Church Farm[60] and part of the Romano-British settlement near Chesterton.

The Earl Bathurst gave the plot of land to the village for the hall's construction, and recycled stone from an old nearby barn was used for the building.