Below is a list of possible1 extant manuscripts. Minor additional fragments and summaries can be found in Dumville***.

For a list of published versions and translations (including some online) see here.

The first column contains the chief reference for the details and the name commonly associated with each manuscript, most of which are letters given by Stevenson*, Mommsen*, or Dumville* (who, unfortunately, all use different schemes - Stevenson is given precedence here). The comments are associated with the first reference unless stated.

Various attempts have been made to divide the manuscripts into groups containing a similar content, possibly based on a number of original exemplars which revised the core text ('recensions'). The table below reflects the recensions division of Dumville's various books and papers, which is, broadly**:

Harleian (829 C.E.)
Vatican (944 C.E.)
Harleian + alterations = Gildasian
Gildasian + alterations from CCCC139 = Nennian
Nennian + Gildasian + some Vatican + notes = Sawley

ID Century Author Manuscript and Details Wonders?
A* (H**) c.1100* [image*] None Harleian MS. 3859(fol.135,b) [owned by Coventus Mont-Albanensis?][Harleian] Yes
B* (R?? *) (K*) End of 12th [image*] None Cottonian MS. Vespasian, D.21(fol.1-17) [Royal 15.A.22+*][written Rochester, Kent*] Yes
C* Mid 12th* / 13th* [image*] None Cottonian MS. Vespasian, B. xxv(fol.126,b) [owned by? Christ Church, Canterbury*] [written in Yorkshire*] Yes (+ Contents list from 1543)
D* (P*) Mid 12th [image*] Gylda Sapiente Cottonian MS. Caligula, A.8, fol.41(?)[written Durham bef.1153][used by, and with Vatican and Arundal notes from, Bale**][Gildasian*] Yes, but imperfect at end
E*(Q*) Begin 13th Gildae Sapientis Cottonian MS. Nero, D.8(fol.63) Yes
F* Begin 14th None Cottonian MS. Vitellius, A.8(fol.90,b) Yes
G** 1381 Nennio/ius & Gilda Sapiente Brit. Muse. Burney, 310(p.315) [siml. to K & N][written Priory of Fenchale, Durham] [Copied from Durham B.2.35*][Nennian?] Yes
H* 13th Gilda Sapiente Royal MS., 13.D.v(fol.38) [owned by St Alban's monast.]) Yes
I* 16th Nennius/Ninio Sapiens Royal MS., 13.B.7 [siml.to G] Yes
K* / CCCC139* 13th* / September 1164* Nennio/Ninnius/Ninio Sapiens (2nd prologue - possibly added) Cambridge Corpus Christi College 139 [written Sawley Abbey Cistercian Abbey, West Riding*][written Durham*][Sawley] Yes*
L** (S*) 13th Nennini/io (2 prologues) Cambridge Uni. Lib. (CUL)/ Public Lib. Ff.I.27(1) [owned by Durham][generated from CCCC139][Originally Sawley Cistercian Abbey, West Riding*][Used by Gale][Sawley] Yes*
Bb* 13th Nennini/io (2 prologues) Cambridge Uni. Lib. (CUL)/ Public Lib. Ff.I.27(2).p.41-64 [Gildasian + Vatican marginalia][written Bury St.Edmunds][Similar to Vatican and N] ?
L2* 13th (but it claims 796) Gilda Sapiente (in same vol. as L)   ?
M* 17th Nennini/io (prob. transcribed from L - 2 prolg.) Glasgow Uni. [Belong. to Dr Hunter, Anatomist] ?
N* 13th but incl. notes from 1166 Nennius/io Sapiente (2nd prologue) [Written? & Owned by Dean&Chapter Durham][Siml. to G&K] ?
O*(N?? Paris 11108*) 12th (but it claims 994) ? Bibliotheque du Roi, Paris, Supplement Latin, 165 ?
P* (Ba*) c.1300* Gildas College of Arms Arundel Collection 30 [Marginalia from Vatican*][written Bury St.Edmunds*][Similar to Vatican and N*] ?
Q* 16th Gilda Sapiente Royal MS. 13.B.15 [siml. to H] Yes
R* 14th Gilda Sapiente Cottonian MS, Julius, D v Yes
Z** Early 10th** / 11th* ? Chartres MS 98 (on flyleaves) [destroyed in 1944] ?
**   Gildas Minor / Sapiente Bodleian 163 (was 2016 in the 1697 Cat.) [Owned by Archbish.Usher] ?
* 16th   C.C.C.Cant. 103 ?
* 14th   Camb.Public Lib. I i, 6, 11 ?
*     [Owned by Ingleby of Ripley, collated by Smith]  
* (M*)(R*) 10th* / 994* /11th* Marc the Anchorite Vatican Reg. 1964 (Paris Latin 9768*) [Owned by Monst.of St.Germain, Paris][Vatican] No
*     Notes in Gale, not found in L [pos. from lost Cottonian MSS destroyed in fire in Cambridge in 1731]  
* (D?? Durham*) Early 12th [additions 1166] [Nennio & added Nennius Eulogium from CCCC139] Durham Cathedral Library MS. B.2.35 [Nennian?] ?
*     St.John’s College, Oxford, MS. 99 [prologue from Cam. Univ. Library Ff.I.27(1)][owned by Jervaulx, perhaps from Bridlington][Nennian] ?
* - may be above     Brit. Mus. Plut. 624.V.28.T [Owned by Sir Simon D'Ewes] ?
* - may be above     Ben'et College Lib. Cambridge  
* - may be above     [Lent by Owen Pughe formerly owned by Selden]  
*     Liege Uni. Library MS. 369C [Kirkstall Cistercian, Yorkshire][Same source as CCCC139][Gildasian?] ?
*   c.1139-1200 Brit.Muse. MS. Cotton Titus A.27 Fol.87r/v & 185v to 186v [Two Harleian fragments] No
8048* 13th C. ? Paris, Bib.Nation. MS. Latin 8048 [Vatican] No?
11702* Early 14th C. ? Brit. Lib. MS Additional 11702 [Vatican][Related to 8084 and M] No?
6274* (Ga*) Early 13th C. ? Paris Bib.National. MS Latin 6274 [Gildasian] ?
Rennes* (Gb*) 15th C. copy of a lost Breton MS. ? Rennes, Arch.Depart. d'Ille-et-Vilaine MS. I.F.1003 [Gildasian] ?
CCC363* (Gc*) Early 16th C. copy ? Cambridge Corpus Christi MS.363 [Gildasian][Pos. that seen by Bale at Balliol] ?
* Late 12th - Early 13th C. ? Rouen, Biblio.Municipale MS 1177 f.289r-297v. [Harlean] ?
  Author alive 1072 Nennius? and Giollacaomhan[Gilla Coemáin]* Lebor Bretnach [in Irish][Various manuscripts] Yes