The city of Cardiff is the county town of the historic county of Glamorgan. A small town until the early 19th century, its prominence as a major port for the transport of coal contributed to its rise as a major city. Cardiff was only made a city in 1905, and proclaimed the capital of Wales as recently as 1955.

Although the Romans established a settlement in the area, Cardiff really grew around its castle, which was developed from a Roman fort by William the Conqueror in 1081. A small town grew up in the shadow of the castle, made up primarily of settlers from England. Cardiff had a population of between 1,500 and 2,000 in the Middle Ages.

In 1404 Welsh revolutionary leader Owain Glyndŵr burned Cardiff –mostly built of wood – but the town was soon rebuilt. In 1536, the Act of Union between England and Wales led to the creation of the shire of Glamorgan, and Cardiff was made the county town.

In the 1790s a racecourse, printing press, bank and coffee house all opened in the town, and Cardiff gained a stagecoach service to London. Despite these advances, the 1801 census found the population was still only 1,870.

However, the town grew rapidly from the 1830s onwards, when the Marquess of Bute built a dock, which eventually linked to the Taff Vale Railway. Cardiff became the main port for exports of coal from the Cynon, Rhondda, and Rhymney valleys. The population grew accordingly. Data provided by www.thegenealogist.co.uk, extracted from the site’s census collections, shows a rapid expansion to 66,000 in 1841 and more than 266,000 in 1901. Much of the growth was due to migration: in 1841, a quarter of Cardiff’s population were English-born and more than 10% had been born in Ireland. By 1881 census, Cardiff was the largest town in Wales.

At its peak, Cardiff’s port area, known as Tiger Bay, became the busiest port in the world and the world’s most important coal port. From the 1890s Cardiff was also established as a major steelmaking centre.

These transformations are reflected in census occupation data gleaned from TheGenealogist. In 1841, agricultural labourers and farmers were still near the top of the list, although alongside colliers and miners. In 1901, coal-related jobs still feature highly, but agriculture has gone in favour of thousands of dock labourers.

After a brief post-war boom, Cardiff docks entered a prolonged decline in the interwar period. Bomb damage during the Cardiff Blitz in World War II included the devastation of Llandaff Cathedral (part of Cardiff since 1922). Since 1916 Cardiff has also been the seat of a Catholic archbishop. Noncon-formism has had a significant presence in Cardiff since the 17th century. The oldest of the non-Christian communities in Wales is Judaism, with a Jewish community established since the 18th century.

TheGenealogist’s data team has also analysed census records for the 10 most common surnames in Cardiff. Unsur-prisingly, Welsh names dominate. Those that differ from the combined England and Wales top 10 include Morgan, Lewis, Rees, John, Jenkins, James, Griffiths, Richards and Phillips (all appearing in both 1841 and 1911). Others that stand out in 1841 include David and Price, and Harris in 1911.

You can research your own roots in Cardiff at Glamorgan Archives. The National History Museum of Wales, with many exhibits showing how our forebears lived, is at St Fagans on the edge of the city; plus there’s the National Museum Cardiff for wider history.