The progenitor of the group, William Laidman, was born about 1762, probably in the vicinity of Penrith. At the time of his marriage in 1801, he was designated 'husbandman', but promoted himself to 'yeoman' in his will, drawn up two weeks before his death in 1826. William's wife, Jane Brown, provided him with five children - William, Margaret, Elizabeth, Jane and John - all born in the period 1802 to 1811.
For William and Jane's daughters Elizabeth and Jane, no progeny beyond their children are known. On the other hand, many generations of descendants of sons William and John have been documented. Early descendants tended to remain in the Cumberland area, but later generations gradually spread northwards into Scotland and to various parts of southern England.
The descendants of daughter Margaret - or, more specifically, of her natural son Thomas Laidman - form an interesting branch of the Cumberland Laidmans. While quite young, probably in his early teens, Thomas left his family in Cumberland and travelled south to obtain employment as a farm labourer in the Kendal area, county of Westmorland. His 1852 marriage to Eleanor Walker produced six children. After Eleanor's death in 1869, Thomas remarried and took his new wife, Alice Brass, and the two youngest of his children eastwards across the country to the coalfields near Durham. However, Alice soon died and Thomas married a third time - to Jane Spoors, by whom he had five more children. Many of their descendants are to be found in the vicinity of Durham, while those of Thomas' older children persist in areas around Ulverston and Lancaster.