Glasgow experienced a sustained period of in-migration between the 1770s and 1830s. Writing in the 1840s, the journalist James Pagan (1811-1870) commented on the remarkable demographic transformation over fifty years with a rise in the number of inhabitants from an estimated 66,500 in 1791 to over 280,000 in 1841, including the suburban districts. A large proportion of incomers came from Lowland Scotland, especially the counties of Ayrshire, Dunbartonshire, Lanarkshire and Renfrewshire. Pagan himself was representative of migratory patterns at the time having been born in Dumfries. The western Highlands also provided a substantial number of Glasgow's migrants, overwhelmingly from Argyllshire. In the early 19th century textile manufacturers actively recruited Highland labour for their cotton-spinning factories.
Glasgow's proximity to Ulster meant that there were close connections with the north of Ireland and these intensified as transport communications became more accessible. Commercial steam-shipping in the 1820s eventually reduced fares from Belfast to as little as 4d a head. Ireland, along with the Scottish Highlands, supplied the bulk of the labour force for harvesting agricultural produce. Glasgow was often the first stepping-off point for these workers who then moved on to rural districts. In the city the Irish served as a reservoir for unskilled, but physically demanding, labour notably in the building trade. They also provided a substantial percentage of the textile workforce. Part of Bridgeton was known as "Wee Belfast" because of the number of Irish handloom weavers who settled there.
While incomers to Glasgow were typically of Scottish or Irish origins, many other nationalities were represented in the migrant profile. For instance, the Dixon family of Govanhill had roots in north-east England and brought in English expertise to help develop their iron works to the south of the city. Papillon Street in Bridgeton was named after the Frenchman who introduced the Turkey-red dyeing process to Glasgow. The city's small Jewish community came predominantly from Germany and the Netherlands. Glasgow's overseas trading connections also meant that there was a significant number of black people in the city, whether from Africa or from North America and the Caribbean. There was a vogue among wealthy Glaswegians in the 18th century to employ black servants, although the status of slavery in Scotland was declared illegal in 1778.