How do the Marchbanks relate to Clan Johnston/e? The story told of the origins of the surname Marjoribanks, is that Marjorie, daughter of King Robert the Bruce, brought into her marriage with Walter Stewart in 1315 lands in Dumfriesshire which became known as "Marjorie's Banks". Unfortunately, there are no records indicating that such lands formed part of Marjorie's dowry. There have been many explanations of the origin of this place name (it is now Marchbank Farm in the parish of Kirkpatrick Juxta near Moffat) but it may have been adopted as a token of respect to Marjorie, since the Bruces at one time owned land in the area.
One belief is that this story was generated by a junior branch of the Marjoribankses in the 17th century to bolster the family’s claim to gentility. The first known Marjoribanks, Philip "de Merioribankis de eodem," i.e. "Marjoribanks of that Ilk," appears in 1485 as the holder of the "five merklands of Merioribankis of ancient extent." Alexander Nisbet, one of the most cited and important authors on Scottish heraldry, asserts that the family who acquired the lands of the princess and took her name were originally kin to the Johnston Lords of Annandale. He finds evidence for this in the Marchbank’s coat of arms, which incorporates a gold cushion and a star. The Clan Johnston/e’s coat of arms bears three gold cushions, and in heraldry a star often alludes to a spur-rowel, which is part of Lord of Annandale’s crest. The assumtion is that the earliest Marchbank was probably a Johnstone who distinguished himself from the many other Johnstones of the area by adopting a family name derived from name of a paternal ancestor.