ONE of the principal pace-setters of economic growth in mid- eighteenth- centuryWales was the rising trend of the population. Although the absence of precise data makes it impossible to reconstruct the demographic structure before 1801, the population of Wales probably rose from around 489,000 in 1750 to 530,000 by 1780. By the time of the first census in 1801, demographic growth was well advanced and Wales's population stood at 587,000. Although demographic trends in this period fluctuated from region to region and even from parish to parish, the decisive upward movement seems to have occurred after 1750. Less prone by then to interruptions caused by mortality crises, population growth became normal and sustained. As famine years dwindled, the gap between the number of births and the number of deaths widened. In rural Radnorshire birth rates drew sharply away from death rates between 1750 and 1770, whilst in Caernarfonshire burials exceeded baptisms in two years only--1762 and 1769--in the period after 1740. In the parish of Aberdare, the excess of burials over baptisms had halted by 1750 and over the following three decades baptisms exceeded burials by twelve, eleven, and twenty-four respectively.
The most notable upsurge of population growth occurred wherever there was quickening economic activity. The counties of Denbigh, Flint, and Glamorgan, in particular, experienced unusually rapid numerical expansion as the birth rate accelerated and as increasing numbers of migrants were attracted to new and wealthy industrial communities. The swiftest growth rates in industrializing counties were found in Flintshire and Glamorgan. Between 1750 and 1801 Flintshire's population increased from 29,700 to 39,622 (an increase of 33-4 per cent), and Glamorgan's population grew from 55,200 to 71,525 (29.5 per cent) in the same period. From the mid- 1740s, particularly, substantial increases occurred in the population of west Glamorgan: the most vital growth-centres were communities such as Llangyfelach, Llansamlet, Cadoxton, Neath, and Swansea, where numbers were rising as a result of considerable developments in the copper and coal industries. Marriage and baptism aggregates increased significantly and the ratio of baptisms to burials rose from 472:346 in 1750 to 710:499 in 1780. Even the epidemic diseases which continued to ravage Wales from time to time were no longer capable of checking the general upward turn in demographic patterns after 1750.