No one knows when or where Harold and Edith Swan-neck met, but their relationship lasted over twenty years. If Edith Swan-neck was the same person as Edith the Fair, then she was a great heiress of lands throughout Wessex, Harold's domain, which then encompassed the lower third of England. Harold and Edith Swan-neck were not united by any recognized Church laws. Their marriage is often referred to as having occurred in the Danish manner, more Danico, or Edith Swan-neck is called Harold's hand-fasted wife under a formal agreement that she and Harold considered each other man and wife. Whatever the appropriate term, this meant that any children from their marriage would be considered Harold's legitimate heirs. And there were children, at least three sons Godwin, Edmund, and Magnus, as well as daughters. There was Gunnhild who first went to Wilton Abbey like her aunt Edward the Confessor's wife, but through a later abduction or escape became the wife of a Norman, Alan Rufus. There was also Gytha, who escaped to Sweden (instead Denmark; thanks to author Carol McGrath for that correction) with two of her brothers and might have married Vladimir II Monomakh, the Grand Prince of Rus, part of a dynasty that would rule Russia until the 16th century. The union between the children's parents also allowed more than one wife, or permitted the husband to easily put aside the wife or keep her in the background, which is an important aspect considering how Harold and Edith Swan-neck's history unfolded.
Edward the Confessor's death in January 1066 and Harold's selection as king of England by the rudimentary parliament set the stage for conflict with the Normans in northern France, but also led to more personal tragedy. For reasons, which remain unclear, Harold married a second time to another Edith, this time the daughter of Earl Aelfgar of Mercia, widowed in 1064. The bride's perspective on her new husband can only be guessed at; she might not have held a favorable view of Harold since he had spent the previous years attacking her first husband, the Welsh ruler Gruffydd ap Lywelyn. How did Edith Swan-neck feel about this union? There's no doubt she remained in Harold's life, but what must she have felt to see another woman call Harold husband and become his official queen-consort, especially one who would soon become pregnant and give Harold more children?
Whatever turmoil might have existed in his private life, Harold had to turn his attention to the defense of England when his enemies King Harold Hadrada of Norway and Duke William the Bastard of Normandy decided to invade England in the fall. Harold defeated the Norwegian king at Stamford Bridge in September 1066, only to lose his life and kingdom to the Normans in the following month. After the battle, Edith Swan-neck had the terrible task of identifying her lover's body because the Normans had mutilated the king so as to make him unrecognizable, yet they needed to eliminate any possibility the English people would continue to revolt if they thought Harold yet lived. It's said Edith Swan-neck identified Harold by a marks or marks on his body that only she who had shared his intimate life would have immediately recognized.
Image of Harold from the Bayeux Tapestry, public domain, sourced from Wiki Commons