All of King Henry’s wives had one thing in common, they all descended from Edward I; some by his first wife Eleanor of Castile or by his second, Marguerite of France; and in some cases both! In Hampton Court Palace in King Henry VIII’s apartment there are six stained glassed windows showing his wives pedigrees from King Edward I. As some were descended multiple times or by both wives the more prominent ancestry was featured.
From Atonia Fraser’s The Wives of Henry VIII, pg 363:
The following genealogy should be seen as a reflection of the narrowness of aristocratic society in a world of small population, rather than as some unconscious desire [that King Henry VIII might have] to commit forms of incest as has been suggested. The wives of Henry VIII were not “closely” related or to King Henry himself. The exception would be of the first cousins Anne Boleyn and Catherine Howard; Henry’s 2nd and 5th wife whom shared the same grandfather, Sir Thomas Howard, 2nd Duke of Norfolk by his 1st wife Elizabeth Tilney (herself the daughter of Elizabeth Cheney by her first husband Sir Philip Tilney. Elizabeth married secondly Sir John Say. Her daughter Anne would become grandmother to Queen consort Jane Seymour, thus making Queen Anne, Queen Jane, and Queen Catherine Howard second cousins).
In actuality, King Henry was closely related to two of his wives; Katherine of Aragon and his last wife, Katherine Parr. All three shared common ancestry and the ancestor Prince John of Gaunt, 1st Duke of Lancaster. Thus, Katherine of Aragon was a 3rd cousin, once removed and 4th cousin (by Lancaster’s first two wives). Katherine’s lineage made her more eligible to the throne of England than her father-in-law, Henry VII. The lineage from both Henry VIII and Katherine of Aragon gave their daughter, Princess Mary, the stronghold that she would have needed to be Queen Regnant from birth. Her claim to the throne was undeniable, yet Henry VIII threw away her chances–when he declared Mary illegitimate and moved on to wife no. 2, Anne Boleyn.
Parr, however, had multiple links via her father and mother. Queen Katherine Parr and Henry VIII’s closest relations: 3rd cousins via Lady Maud Parr (through Sir Richard Wydeville and Joan Bedlisgate; grandparents of Queen consort Elizabeth Woodville, wife of Edward IV); and by Lord Parr — 3rd cousins, once removed (through Ralph Neville, 1st Earl of Westmorland and Lady Joan Beaufort; parents to Lady Cecily, Duchess of York, mother to Edward IV and Richard III); 4th cousins by John of Gaunt, 1st Duke of Lancaster and Katherine Swynford (grandparents to John Beaufort, 1st Earl of Somerset); 4th cousins, once removed and 5th cousins through Sir Thomas Holland, 2nd Earl of Kent and Lady Alice FitzAlan (parents of Lady Margaret, Countess of Somerset and Lady Alianore, Countess of March).
The Hampton Court Pedigrees
linking them all back to King Edward I of England
Queen Katharine of Aragon
“Not for my Crown” (As Princess of Wales)
“Humble and Loyal” (As queen consort)
Katharine of Arragon 1st wife of King Henry ye Eighth, her pedigree from King Edward ye First and his 1st wife Eleanor of Castile
Katharine of Aragon was the daughter of
Queen Anne Bullen
“The Most Happy“
Anne Bullen the 2nd wife of King Henry ye Eighth, her pedigree from King Edward ye First and his second wife Margaret of France
Anne Bullen, daughter of
Queen Jane Seymour
“Bound to Serve and Obey“
Jane Seymour 3rd wife of King Henry ye Eighth, her pedigree from King Edward ye First and his 1st wife Eleanor of Castile
Jane Seymour was the daughter of
Queen Anne of Cleve
“God Send Me Well to Keep“
Anne of Cleve, 4th wife of King Henry ye Eighth, her pedigree from King Edward ye First and his 1st wife Eleanor of Castile
Anne of Cleve was the daughter of
Queen Katharine Howard
“No Other Will But His“
Katharine Howard, 5th wife of King Henry ye Eighth, her pedigree from King Edward ye First and his 2nd wife Margaret of France
Katharine, daughter of
Lord Edmond Howard
Queen Katherine Parr
“To be Useful in All That I Do“
Katharine Parr, 6th wife of King Henry ye Eighth, her pedigree from King Edward ye First and his 1st wife Eleanor of Castile