The surname of AGGAR was a baptismal name 'the son of Hagard' an ancient font name, now forgotten. The name was also used as a technical term in falconry to denote a hawk that had been captured and trained when already fully-grown, rather than being reared in captivity, and the surname could have therefore conceivably have developed as an occupational name for a falconer. Early records of the name mention Ivo Hacgard, County Suffolk, 1273. Thomas Hagar, of Yorkshire, was listed in the Yorkshire Poll Tax of 1379. Richard de Haghous, 1400 County Surrey. The name is also spelt Hagger and Haggard.

The English writer Sir H Rider Haggard (1856-1925) was born into the landed gentry in County Norfolk. His family were descended from a Danish nobleman, Andrew Ogard, who came to England in the fifteenth century from the city of Agard in Denmark.

The earliest hereditary surnames in England are found shortly after the Norman Conquest of 1066 and are of Norman French origin rather than native English. On the arrival of the Normans they identified themselves by references to the estates from which they came in northern France. These names moved rapidly on with their bearers into Scotland and Ireland. Others of the Norman Invaders took names from the estates in England which they had newly acquired.

The associated arms are recorded in Sir Bernard Burkes General Armory. Ulster King of Arms in 1884.