Jane Seymour may have first come to court in the service of Queen Catherine, but then was moved to wait on Anne Boleyn as she rose in the King's favor and eventually became his second wife.
In September 1535, the King stayed at the Seymour family home in Wiltshire, England. It may have been there that the king "noticed" Jane. But, it isn't until February of 1536 that there is evidence of Henry's new love for Jane.
By that point, Henry's disinterest in Anne was obvious and Jane was likely pegged to be her replacement as Queen.
Opinion is divided as to how Jane felt about being the new object of Henry's affections. Some see Jane's calm and gentle demeanor as evidence that she didn't really understand the position as political pawn she was playing for her family. Others see it as a mask for her fear. Seeing how Henry's two previous Queens had been treated once they fell from favor, Jane probably had some trepidation, although Anne Boleyn's final fate had not been sealed at that time.
One other view was that Jane fell into her role quite willingly and actively sought to entice the King and flaunt her favor even in front of the current Queen.
How Jane actually felt, we will never know. Henry's feelings were pretty clear though. Within 24 hours of Anne Boleyn's execution, Jane Seymour and Henry VIII were formally betrothed. On the 30th of May, they were married. Unlike Henry's previous two Queens, Jane never had a coronation. Perhaps the King was waiting to Jane to 'prove' herself by giving him a son.
Less than two months after Henry and Jane's marriage, the Duke of Richmond, Henry Fitzroy died at the age of 17. Fitzroy was the King's bastard son by his mistress Elizabeth Blount.
It wasn't until early 1537 that Jane became pregnant. During her pregnancy, Jane's every whim was indulged by the King, convinced that Jane, whom he felt to be his first 'true wife', carried his long hoped for son. In October, a prince was born at Hampton Court Palace and was christened on 15th of October. The baby was named Edward. Mary, daughter of Catherine of Aragon, was godmother and Elizabeth, daughter of Anne Boleyn, also played a role in the ceremony.
There has been much written over whether or not Jane gave birth to Edward by cesarean section. It seems unlikely that if she had, she would have lived as long as she did after the birth. Jane attended her son's christening, although she was weak. She died on October 24th, just two weeks after her son was born.
Henry had already been preparing his own tomb at St. George's Chapel at Windsor Castle, which was where Jane was buried. In the end, she would be the only of Henry's six wives to be buried with him.