Born on Christmas Day 1281 at
Denbigh Castle, Alice was the only daughter and heir of
Henry de Lacy, Earl of Lincoln and
Margaret Longespée, Countess of Salisbury suo jure (in her own right). Her mother Margaret was the granddaughter of the prince of North Wales,
Llywelyn ab Iorwerth, and the great-granddaughter and ultimate heir of one of the illegitimate sons of
Henry II of England, William Longespée (Longsword), whose nickname became his surname. Tragic accidents resulted in the deaths of Alice's two brothers in childhood. Edmund drowned in a well at
Denbigh Castle and John fell to his death from a parapet at
Pontefract Castle. This made Alice the
heir presumptive to two earldoms, one from her father and one from her mother, which she would inherit if her parents had no further children. With Alice belonging to such an influential and wealthy family, King
Edward I arranged for her betrothal "in her 9th year" to his nephew,
Thomas of Lancaster, himself heir to the earldoms of Lancaster, Leicester and Derby. They were married on 28 October 1294, when Alice was 13 years old and Thomas about 16. By this time, the probability of Alice's parents begetting a male heir had considerably diminished, and the marriage settlement reflects the strong probability that Alice would be one of the great heiresses of the land. The bulk of her vast inheritance from her father, which included the Earldom of Lincoln and many other estates, was to go to Thomas, with reversion to Thomas's heirs. In other words, even if Alice and Thomas had no children together, her estate would devolve upon her husband's heirs rather than upon her blood relatives. Also, if Alice outlived Thomas, then on her own death, her father's inheritance would pass to Thomas's heirs as her father had come to an agreement with the King that, should Alice have no children, her father's Earldom of Lincoln would pass into the royal family on her death. The marriage was not successful. The couple had no children, and they lived quite separate lives. Alice mostly lived alone in her castle of Pickering, Yorkshire, while Thomas took a host of mistresses and fathered at least two illegitimate children. ==Countess==