George Gordon Byron was born in London on 22 January 1788, just off Oxford Street, in a house which is now part of Selfridge's Department Store. His mother was Scottish, and as is common Scottish practice, her family name of Gordon was incorporated into his. In fact the poet's parents had sporadically taken the name Gordon, possibly to ensure the Gordon inheritance. His father, John Byron, was from a junior branch of an English aristocratic family, the Byrons of Newstead and Rochdale, and the fifth Baron was the newly born Byron's great uncle. Byron's father was already a widower, with a daughter, Augusta, who was to play a considerable role in the poet's life. Some reports have his first wife driven early to her grave by her husband's profligacy, and profligate he certainly was, though by all accounts also charming and amenable. His own father had also been easy with both women and money, but had also earned as a vice-admiral in the Navy considerable respect for his fearlessness (he was known as ‘Foulweather Jack’). Initially Byron's parents had lived in her ramshackle castle at Gight near Aberdeen, but pressed by his creditors they had decamped to France, from which Mrs Byron returned in order to have her son born in England. The first year of Byron's life was passed on the run from those creditors, but by summer 1789 his mother had settled in Aberdeen. His father seems only to have been present intermittently, finally vanishing to France where he died in 1791.

Byron was then the heir both to a Scottish Calvinist tradition – his mother was not well educated, and a superstitious believer – and to a distinctly cavalier and swashbuckling English heritage. He was also born with a lame right foot, a fact of which the young boy was extremely self-conscious, and which the man never quite forgot. Such a congenital defect was sometimes thought of in superstitious Calvinist circles as a mark of Cain, a signal of damnation. This was a way of thinking which from time to time oppressed the poet, but of which he also made creative use.