Ancestral Roots has Agnes m. Adam II de Brus, but that has been changed.
The following two posts to soc.genealogy.medieval indicate that the "accepted" order of wives for Adam I & II de Brus should actually be reversed:
From: Rosie Bevan (rbevan@@paradise.net.nz)
Subject: Re: Domesday Descendants corrections: Harcourt & Brus
Newsgroups: soc.genealogy.medieval
Date: 2002-06-05 18:38:09 PST
Hi Cris
As you have commented, K. Keats-Rohan in Domesday Descendants [p.354, 355] has listed Adam I de Brus of Skelton(d.1142) as married to Agnes of Aumale, and Adam II Brus (d.1196) as married to Juetta de Arches. This is in variance with Farrer's observations in vol. 3 of Early Yorkshire Charters in which the opposite placement is upheld. The situation is not helped by CP which claims [VII : 670] that Agnes of Aumale married William de Roumare and secondly Piers de Brus.
A study of the chronology tends to support K-R's findings.
Stephen de Aumale, Agnes' father, came of age in 1090, indicating that he was born about 1069. He married Hawise de Mortemer and they had 3 sons (William, Ingelram and Stephen) and 3 or 4 daughters (Matilda, Adelisa are names of two), of whom Agnes was supposedly the youngest. and about 1127.[CP VII : 670 ; K-R Domesday Descendants p.225]. Stephen's son and heir is mentioned in a charter of 1115. [EYC 3; no 1304]. Assuming this is William le Gros, he was born before 1109, as he was of age in 1130. At a rough guess based on the dates of William le Gros, as a younger child Agnes would have been born between 1110-1120. This would place her more appropriately as wife of Adam I, than Adam II, as the latter was born in 1134 (of age in 1155). On the death of Adam I de Brus she had borne two sons - Adam and William. Adam the younger was placed in the custody of William le Gros, Count of Aumale.
The only piece of evidence which supports a marriage between the Brus/Aumale families is the claim in 1276, on the death of Avelina de Forz without issue, some 150 years after the supposed event, of the four coheirs of Peter de Brus to the Holderness estate. Walter de Fauconberg and Agnes, Marmaduke Thweng and Lucy, Margaret widow of Robert de Ros, John de Bella Aqua and Laderina claimed to be heirs by descent from Agnes de Aumale.
Agnes de Aumale married [secondly] William de Roumare and had three sons (William, Robert and Roger) by him before his death in 1151 [K-R DD: p.670]. The eldest, William later Earl of Lincoln was still a minor in 1165 so was born later than 1144. This certainly fits within the chronology as Adam I died in 1142.
-snip-
Cheers
Rosie
Note; I corrected the above message, based on a later correcting post by Rosie; the original message said that Stephen de Aumale succeeded his father who d. in 1127, when Stephen himself d. in 1127.
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From: Cristopher Nash (c@@windsong.u-net.com)
Subject: Re: Domesday Descendants corrections: Harcourt & Brus
Newsgroups: soc.genealogy.medieval
Date: 2002-06-08 04:13:25 PST
Now I can quickly summarize the argument of Ruth Blakely, 'The Bruses of Skelton and William of Aumale' in _Yorks Archeol Jnl_ (2001) 73:19-28, which appears to be the clincher leading Keats-Rohan in DD to reverse the traditional order of two early Brus marriages, giving (1) the wife of Adam I de Brus as Agnes d'Aumale and (2) the wife of Adam II de Brus as Juetta de Arches. Blaklely's article is devoted specifically to this double question.
-snip-
On Agnes d'Aumale: Again Blakely starts with William Brown's reversal. A claim to the Aumale estate put forward in 1274 by the heirs of Peter III de Brus has regularly been accepted in evidence that the later Bruses were descended from Agnes, and Blakely does not question this. She gives evidence on chronological grounds that Agnes could not have been the wife of Robert I de Brus (Adam I's father) or of Peter I de Brus (Adam II's son), and then provides an argument for her having been the wife of the remaining possible Brus, viz. Adam I, and makes out a case for her having been married to her other husband, William II de Roumare after (not before, as some accounts have it) her Brus marriage [25-27]. The details are intricate and I'm not going to unpack them all here. Her conclusion is that "although the evidence is less conclusive than in the case of Juetta, there are sufficient pointers to suggest that this was indeed the case" and "well within the bounds of probability" [26, 27].
An important aspect of Blakely's argument is that this reconstruction of the 4 marriages of Juetta and Agnes resolves a number of problems that have long dogged the Brus genealogy. A useful part of its development is a thoughtful assessment of the historical (inter-family political/economic) background to these events. Rosie, I think when your interloan copy gets to you you'll find that the article parallels a good part of your smart chronological case, and yours may in fact lend it further support.
Hope this quick sketch helps.
Cris