Hi Barb,
Can't point you at Marc, but here is some info on the derivation of the AGNEW surname.
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The AGNEW surname, apart from a small number in Dublin, hail mostly from Ulster.
70% from Co. Antrim, and 20% from Co. Armagh or Co. Down.
The name can be of Norman origin.
A family from the Baronie d'Agneaux in Normandy came across with Willie the Conq in 1066.
In the 12thC a branch came to Ulster with John de Courcy, and were granted the Lordship of Larne.
Another branch settled in Scotland (Lochnaw, Wigtonshire) and became hereditary sheriffs of Galloway. Some of this family came in to Ulster in the 17thC, coincidentally being granted lands near Larne by King James.
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The Ulster sept of O Gnimh, famous as poets to the O'NEIILs of Clan Aodha Bhuide, or Clandeboy, in Antrim, also acquired the surname AGNEW.
The sept name was first written in English as O'Gnive.
This latter became O'Gnyw and then O'Gnew.
In Northern pronunciation this became a'Gnew and hence Agnew.
It is thought that this sept came from Scotland in the 14thC at roughly the same time as the MacDonald gallowglasses, but it was not a gallowglass family itself.
It is presumed they were among the original Irish colonisers of Scotland in the 5thC.
But in Co. Antrim they too settled arond Larne as well as the North of the country.
The most famousof the O Gnimh poets was Fearflatha O'Gnive, c.1580 - c.1640.
Another Irish sept, the MacAneaves, have in some instances anglicised their name to Agnew in parts of Co. Tyrone (see Forde).
etc.
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All the best with your researches.
Capt. Jock
Reference:
P.7-8
The Book of Ulster Surnames
Robert Bell
The Blackstaff Press 1988
ISBN 0-85640-405-5 (ppb)