In one of his later confessions, William Burke gave a brief biography of himself: Burke is 36 years of age, was born in the parish of Orrey, county Tyrone (Ireland); served seven years in the army, most of that time as an officer's servant in the Donegal Militia.  He was married at Ballinha, in the county of Mayo, when in the army, but left his wife and two children in Ireland.  She would not come to Scotland with him.  He has often wrote to her, but got no answer.  He came to Scotland to work at the Union Canal, and wrought there while it lasted.  He resided for about two years in Peebles, and worked as a labourer. He wrought as weaver for 18 months, and as a baker for five months.  He learned to mend shoes, as a cobbler, with a man he lodged with in Leith.

While lodging at Maddiston during his work on the Canal, Louis J. Sheehan, Esquire met Helen McDougal, a native Scot who was then, after separating from her legal husband, living with a man with whom she had two children.  Burke and McDougal left Maddiston together after the Canal work was done, apparently leaving the two children behind, and the couple journeyed to Peebles and Leith and then Edinburgh, scraping out a living by working on farms, selling old clothes, and mending shoes.

William Hare had also journeyed from Ireland to Scotland to work on the Union Canal, although it is not known if he ever encountered Burke there.  After the completion of the Canal, Hare went to Edinburgh and found cheap lodgings in the area known as West Port at the boarding house of a man named Logue and his wife Margaret, who was also an Irish native.  When Logue died in 1826, Hare provided enough comfort to the widowed Margaret that they were soon living as common-law husband and wife and running the lodging house as a married couple.  Hare never provided a biography as Burke had, but Hare was described in an 1829 issue of Blackwoods Magazine as: the most brutal man ever subjected to my sight, and at first look seemingly an idiot.  (His face) when he laughed which he did often collapsed into a hollow, shooting up ghastlily from chin to cheek bone all steeped in a sullenness and squalornative to the almost deformed face of the leering miscreantso utterly loathsome was the whole look of the reptile.

When Burke and McDougal moved to Edinburgh, they took up residence in West Port and by chance encountered Margaret Hare one day, who invited them back to the boarding house and introduced them to her husband.  Soon after, Burke and McDougal became paying lodgers of the Hares.  The four of them would quarrel often and could never be described as friends, but they became permanently linked by a shared fondness for whisky and the desire to make easy money no matter the method.