Originally Posted by Duc_et_Pair
The King is no direct descendant, from father or mother, to Saxon Kings. With some zig-zagging and hop-hopping descendance can be traced. The late Duke of Edinburgh was a direct descendant of the Schleswig-Holstein-Sonderburg-Glücksburgs and the Battenbergs. The late Queen was a direct descendant of the Sachsen-Coburgs and the Bowes-Lyons.
Alfred The Great's daughter Ælfthryth married Baldwin II, Count of Flanders and Charles III is a direct descendant of that marriage via:
Ælfthryth and Baldwin II
Arnulf I, Count of Flanders
Baldwin III, Count of Flanders
Arnulf II, Count of Flanders
Baldwin IV, Count of Flanders
Baldwin V, Count of Flanders
Matilda Queen of England (married William the Conqueror or William I)
John of Gaunt
John Beaufort 1st Earl of Somerset
John Beaufort Duke of Somerset
Lady Margaret Beaufort
Margaret Queen of Scots
Mary Queen of Scots
James VI and I
Elizabeth Queen of Bohemia
Electress Sophia of Hanover
Frederick Prince of Wales
Edward Duke of Kent
That means that Charles 37th great grandfather is Alfred the Great.
I am sure there are other lines of descent which may be shorter or longer but Charles is a direct descendant from the Anglo-Saxon Kings down to Alfred the Great.
I have found an even closer line - direct descendant from Edmund Ironside the second last King of the House of Wessex via his granddaughter St Margaret. Her father was Edward the Exile who had he lived would have been the heir to Edward The Confessor. St Margaret's daughter Edith married Henry I and from their daughter Matilda as shown above Charles does descend.
Edward the Exile
St Margaret, Queen of Scots
Matilda - Queen of England as wife of Henry I (direct descent is listed above)
This makes Charles a 32 great-grandchild of the second last King of England from the House of Wessex another Anglo-Saxon King.