The Glendinnings are a sept of the Douglas Clan and the history of the name goes back to Adam de Glendonwyn who was alive during the reign of Alexander III of Scotland, circa 1286.

Educated men in Scotland spoke the language of their allies, the French, and many surnames developed based on place names - de Glendonwyn meaning of (or from) Glendonwyn.

Adam's descendants became knights and substantial landholders, fighting alongside the Douglas clan leaders in their battles with the English and were often to be found offering themselves to English Kings as hostage for their countrymen's good behaviour.

The clan grew (that is the followers who took the name Glendinning and who were not necessarily relations of the principal family) and ultimately began to spread - across the border to England, over to Ireland during the Plantation of Ulster in 1610 and on to the New Worlds, Scots being leaders in emigration.

The most common reasons for the earliest border crossings were raids to steal English sheep, cattle and horses. Some of these men, known as reivers, just never went home and were eventually accepted by the community they chose to settle in.