In older times in Scotland, the prefix ‘Mac’ or ‘Mc’, and the suffix ‘son’ all meant ‘son of’. These terms all come from the times when Scots used the patronimic versions of their names. For example, a Scot might call himself ‘James, son of Robert, son of James….’ and so on.
By about the early 1600’s the English were instrumental in introducing surnames to Scotland. The person who described himself as ‘James, son of Robert…" was then called ’James Robertson’, but might also be known as James MacRobert or McRobert. These versions of the name were used interchangeably.
Another consideration is the languages used in Scotland. In older times, Gaelic was the commonly used language, but this developed into Broad Scots, then English more recently. Also, as many of the population were illiterate, records were kept by those who wrote down what they were told by others. The Old Parish Records of Scotland show many different spellings of the same name; those recording in different areas used their own version of a name, as well as abbreviations for many names.
It seems that in Broad Scots, ‘K’ and ‘F’ and ‘Ph’ are the same sound, so that ‘Kerras’ is the same name as ‘Fergus’ and ‘Fhearghuis’, and so McFergus is the same as Fergusson or McKerris – in any of its possible spellings.
“The Surnames of Scotland” by George F. Black (page 526) lists “Mackerras” as “From M’Fhear’us or MacFhearghuis” (son of Fergus).
A search for early mention of the name finds references from the 1200’s onward. ‘The Chiefs of Grant’, volume 3, shows that “Willelmus McRobert McKerwyss” (that is, William, son of Robert, son of Fergus) and “Finlaius McRobert McKerwyss” (that is, Finlay, son of Robert, son of Fergus) were parishioners involved in the election of the Parish Clerk of Duthil in 1537. One possibility is that the original Fergus above (that is, the grandfather of William and Finlay) may be the source of our surname. It also seems that Fergus would have been a much used family name in the area, and this is the case in the Grant family, which is centred originally around Duthil. The researcher consulted at Inverness Library Family Heritage Centre, Alistair Macleod, suggested that we may be either descended from the Grants, or perhaps married into the Grants, a very strong local family (or clan).
‘The Scots Peerage’, volume 8, pages 242-243 shows that Earl Gilbert (d. 1223 aged approx. 73) of Strathearn (the area east of Loch Earn), had children including Robert (his heir, who became Earl in 1210 or 1223) and Fergus, who may have succeeded his uncle Malise (or Mallus). This Fergus was remembered as having granted land to various abbeys and he received the rank of knighthood. He died in about 1247. The Earls of Strathearn had land holdings both in Strachur (Strathearn) and Moray (based around Glencairnie in Strathspey). Either this Fergus or perhaps a nephew of the same name could also be the source of the Mackerras name in the Moray area.
The name appears in 1483, 1499 and onwards; for example, Johne McKerris of Kentyr (“place at head of loch”), a mention in 1519 in “The Thanes of Cawdor”, page 130 as a witness; in 1547 lands were granted to Makane V’Kerris and his son Gillebarchane (OPS II p78); in 1575 Johne M’Kearrois, Inverness (Mill, ‘Plays’, p 257).
It appears we come from an old race both in Strachur (in the Argyll area) and Moray (in the Highlands). Generally, the Mackerrases in the world today seem to come from the Moray area of Scotland, while in past times there was another family group of Mackerrases from the south of Scotland in the Argyll area. There is no obvious evidence that the two were actually related; they both would have descended from an original Fergus, but not necessarily the same Fergus.
The branch from the south of Scotland were recognised as members of the Fergusson Clan centuries ago, as the two surnames mean the same (son of Fergus), and they came from the same geographical area. Indeed there is a hand-drawn Fergusson family tree in the main library in Aberdeen showing the Fergusson family of Dunfallandy in Perthshire as having evolved from “Adam Fergusson or Mackerras”. The Fergusson Clan today still recognises the name ‘Mackerras/McKerras’ as a sept of the Fergusson clan.