Nielsen Hayden genealogy
Descendants of Peter fitz Assulf
- Bef 1143Father: Essulf (of Birkin, Yorkshire, England - Bef 1159)
Peter fitz Assulf (of Birkin, Yorkshire, England - Bef 1143)
   └─ Adam de Birkin (of Laxton, Nottinghamshire, England - 1185)
    Maud de Cauz ( - Bef 25 May 1224)
       └─ (Unknown) de Birkin
        Robert le Vavasour (of Addingham, Yorkshire, England - Bef 1228)
            + Theobald Walter ( - Bef 14 Feb 1205 bur.Owney Abbey, Limerick, Ireland)(m. Bef 1201)
            + Fulk III Fitzwarine (of Whittington, Oswestry, Shropshire, England - Bef 22 Nov 1235)
            (m. Bef 1 Oct 1207)
            (m. Bef 1 Oct 1207)