2nd President John Adams was related to John King of England of British royalty through marriage, however he was also related to French royalty by blood.
John, King of England — Isabelle of Angouleme
Henry III, King of England — Eleanor of Provence
Edward I, King of England — Eleanor of Castile
Edward II, King of England — Isabella of France
Edward III, King of England — Philippa of Hainault
John of Gaunt — Catherine Roet
Henry Beaufort — Unknown
Jane Beaufort — Sir Edward Stradling
Sir Henry Stradling — Elizabeth Herbert
Thomas Stradling — Janet Mathew
Jane Stradling — Sir William Grifith
Dorothy Griffith — William Williams
Jane Williams — William Coytmore
Rowland Coytmore — Katherine Miles
Elizabeth Coytmore — Capt. William Tyng
Anna Tyng — Rev. Thomas Shepard
Anna Shepard — Daniel Quincy
Col. John Quincy — Elizabeth Norton
Elizabeth Quincy — Rev. William Smith Jr.
Abigail Smith — President John Adams
Henry III, King of England — Eleanor of Provence
Edward I, King of England — Eleanor of Castile
Edward II, King of England — Isabella of France
Edward III, King of England — Philippa of Hainault
John of Gaunt — Catherine Roet
Henry Beaufort — Unknown
Jane Beaufort — Sir Edward Stradling
Sir Henry Stradling — Elizabeth Herbert
Thomas Stradling — Janet Mathew
Jane Stradling — Sir William Grifith
Dorothy Griffith — William Williams
Jane Williams — William Coytmore
Rowland Coytmore — Katherine Miles
Elizabeth Coytmore — Capt. William Tyng
Anna Tyng — Rev. Thomas Shepard
Anna Shepard — Daniel Quincy
Col. John Quincy — Elizabeth Norton
Elizabeth Quincy — Rev. William Smith Jr.
Abigail Smith — President John Adams
Henry I of France – Anne of Kiev
Hugh Capet – Basilla Flaitel
Hugh de Gournay III – Beatrix de Vermandois
Hugh de Gournay IV – Milesende de Coucy
Hugh de Gournay V – Lady Julia de Dampmartin
Hugh de Gournay VI – Unknown
Anselm de Gourney – Eve Gaunte
Lord John Gourney – Unknown
Elizabeth Gourney - John Apadam
John Apadam – Unknown
William Ap Adams – Unknown
John Ap Adams – Unknown
Thomas Adams – Unknown
Sir John Adams – Unknown
John Adams – Clare Powell
Roger Adams – Jane Elyott
Thomas Adams – Mary Upton
John Adams – Jone Kinnlegh
John Adams – Katherine Stebbing
John Adams – Margarey Squire
Henry Adams – Rose Stebbing
John Adams – Agnes Stone
Henry Adams – Edith Squire
Joseph Adams – Abigail Baxter
Joseph Adams – Hannah Bass
John Adams Sr. – Susanna Boylston
President John Adams
Hugh Capet – Basilla Flaitel
Hugh de Gournay III – Beatrix de Vermandois
Hugh de Gournay IV – Milesende de Coucy
Hugh de Gournay V – Lady Julia de Dampmartin
Hugh de Gournay VI – Unknown
Anselm de Gourney – Eve Gaunte
Lord John Gourney – Unknown
Elizabeth Gourney - John Apadam
John Apadam – Unknown
William Ap Adams – Unknown
John Ap Adams – Unknown
Thomas Adams – Unknown
Sir John Adams – Unknown
John Adams – Clare Powell
Roger Adams – Jane Elyott
Thomas Adams – Mary Upton
John Adams – Jone Kinnlegh
John Adams – Katherine Stebbing
John Adams – Margarey Squire
Henry Adams – Rose Stebbing
John Adams – Agnes Stone
Henry Adams – Edith Squire
Joseph Adams – Abigail Baxter
Joseph Adams – Hannah Bass
John Adams Sr. – Susanna Boylston
President John Adams