Look for Andre du Chesne History of the House of Bethune Paris 1639
A History of the Bethune Family (Translated from the French of Andre du Chesne, with Additions from family records and other available sources)
Together with a sketch of the Faneuil Family with whom the Bethunes have become connected in America
By Mrs. John A. Weisse New York Trows Printing and Bookbinding Co, 201-213 East Twelfth Street 1884
It details pretty much what happened to Bethune Lord Balfours line post its move to the colonies. Ms. Weiss claims that Badouin of France was married to Richard the Lionhearted's cousin after being held prisoner with the King in Germany during their return from the crusades. This was the line of the Balfours that were well known. This line moved to the United States in 1724.
The first George Bethune(1) came to Boston circa 1724 and married Miss Carey. Two sons Nathanial and George(2), one daughter Jane. Nathanial died unmarried. George(2) married Mary Faneiul daughter of Benjamin Faneiul (brother to Peter Faneiul who built Faneiul hall in Boston.) Jane married Mr. Prince
You can find more about that line as there is a brief history of the disowned George Bethune(2) cousin and heir of the last Lord Balfour (Henry)in the Harvard University history (Sibley Shipton?)book as well. He was a classmate of John Adams (who disliked him intensely. Also remember a class at Harvard back then may only have had 20 students). The title passed to Colgerton Bethune of Balfour by special act of British Parliament around 1740-1754.
Bethune(2) sided with the British and his best friend was Edmond Dunkin whose brother was Chief Justice of the English Colony in India. The Dunkins boast a chief justice of South Carolina who had many descendants. His wife was Anne Bethune, daughter of George (2) and Mary Faneuil.
George Bethune(2) married Mary Faneuil in Boston. They had a son named George(3) anddaughters names Susan (Mrs. Edmond Dunkin),Penelope (Mrs. English, whose son George Bethune English is a minor historical figure a friend of John Quincy Adams and a real oddball, he is mentioned in The White Nile written by Alan Moorehead, was a prolific religious writer and at one point a Muslim in the service of the Pasha, he also left a book describing his adventures leading the Pasha"s artillery up the Nile. ), Jane (Mrs. William Hunt), Ann (Mrs. Lovell).
The male line of the Balfour Bethunes continues throughGeorge (4) in the United States. (Though it may be renewed elsewhere as the extremely famous Lord Balfour was from a Different family entirely come the late 19th century)
George Bethune (3) I think married Mary Amory of Boston and they had a son named George Amory Bethune.(4) He was alive and a MD in Boston at the time that Ms. Weiss wrote her book. Ms. Weiss" book stops at this point.
Other names associated with the Bethune family included at the time, Adams, English, Jones and Willard in Boston, Gilman, Robbins, Stein and Weisse in New York, Makepeace in Baltimore and Alston, Dunkin, Huger and Hunt in South Carolina.
John Adams mentions Dunkin (spelled Duncan) as a good friend to Bethune. Sir William Dunkin (who was elder brother to Edmond Dunkin) was the British Chief Justice of India. Edmond was sailing to join him when he was taken prisoner by a privateer during the civil war.