The Earl of Eglinton had a brother, Sir John Seton of St Germains in
East Lothian, who married Margaret Kellie. He does not seem to have been the letter writer, as the Earl of Eglinton's brother,
George Seton, 3rd Earl of Winton calls John Seton the correspondent their cousin. Letters from two cousins called Sir John Seton survive.
Sir John Seton of the French King's Guard John Seton, the letter writer, was a Lieutenant of the
French Royal Guard, the
Gardes Écossaises. There were three John Setons answering this description. The Earl of Eglinton had a cousin, John Seton, the younger son of
William Seton of Kylesmure, who is said to have served in France with Colonel Hepburn. Another cousin, John Seton, was a younger son of John Seton and Isabel Balfour of Carriston, at
Star in
Fife, and a grandson of
George Seton, 6th Lord Seton. He married a daughter of the Comte de Bourbon (perhaps a daughter of
Charles, Count of Soissons). Their only child was a daughter, who married the Hepburn laird of "Adinston" (possibly
Hadddington) in
East Lothian, a relative of the soldier
John Hepburn. Another Scottish soldier of the
Thirty Years' War,
Alexander Seaton, may have been the brother of the letter writer.
Sir John Seton of Gargunnock According to Edward Dunbar Dunbar, the letter writer was John Seton of Gargunnock, the husband of Margaret Hamilton of Elieston (
Illieston House), the widow of
John Stewart of Methven. Dunbar published a letter to Sir Robert Gordon signed "Johan Seton" and dated London 6 June 1636, mentioning a Polish ambassador in London. Seton's brother (possibly Alexander) had approached the ambassador seeking employment. Lord Herries would bring the letter to Robert Gordon. Seton by courtesy calls Gordon his father. In July 1638 a Sir John Seton was in London and was asked by Sir Henry Bruce if he would serve in Scotland for Charles I against the
Covenanters in the
Bishop's War, he replied he would fight for the king but not in his own country, "where his life was". The historian
Steve Murdoch notes that this Seton was a Colonel in the Swedish army. Sir John Seton of Carchunoth had brought 1,200 Scottish recruits from the
Dutch Republic to
Bohemia in 1619. Seton was the military governor of
Třeboň in Bohemia in 1620, while Henry Bruce commanded
Mikulov in
Moravia. The governor of Hagelburg (in 1638), Colonel Thomas Thomson, another officer of the
Gardes Écossaises, later partnered with
John Clerk of
Penicuik and bought soft furnishings in Paris for the
Earl of Lothian. "Carchunoth" was
Gargunnock in
Stirlingshire. The commander in Bohemia was a member of the
Seton of Touch branch of the family, and a more distant cousin of the Earl of Eglinton than the son of the lairds of Carriston or Kylesmure. Two Colonels, James Seton of Gargunnock (in Swedish service) and his brother John Seton or Seaton are recorded in this period.
Thomas Urquhart mentions these brothers in
The Jewel, calling both "James". ==Letters to the Earl of Eglinton==