The following is from Britannia by William Camden:
The Division of Britaine
NOW let us addresse our selves to the Division of Britaine. Countries are divided by Geographers either Naturally, according to the course of rivers and interpose of mountains; or Nationally, according as the people inhabite them; or Diversely and Civilly, according to the wils and jurisdiction of Prince. But forasmuch as wee shall treat here and there thorowout this whole worke of the first and second kinds, that third (which is civill and politike) seemeth properly pertinent to this place. Which yet is overcast with so darke a mist, though the iniquitie of former times, that much easier it is in this case to confute what is false, than to find out the truth.
2. Our Historiographers will needs have that division of Britaine to be most antient whereby they divide it into Loegria, Cambria, and Albania, that is, to speake more plainly, into England, Wales, and Scotland. But I would think this division to be of a newer and later edition, both because it is threefold, for it seemeth to have risen of those three sorts of people, English, Welch, and Scotish, which last of all parted the Iland among themselves: and also for that such a partition is no where extant in approved authors before our Geffrey of Monmouth. For the fable (as the Criticks of our age doe thinke) could not hang well together unless he the said Geffrey had devised three sonnes of Brutus, to wit, Locrine, Camber, and Albanact, because so many Nations flourished here when hee lived. Neither make they doubt but he would have found out more children of Brutus, if there had beene more nations distinct at the same time in Britaine.
3. The most antient division of Britaine, in the opinion of many learned me, is that which is found in Ptolomee, in the second booke of Mathematicall Construction, where he treateth of the Parallels: namely, into Britaine the Great and the Lesse. But by their leave, as great learned men as they be, they themselves shall see, if it please them but to examine thorowly and exactly in that place, the proportion of distance from the Aequator, and compare the same with his Geographicall Description, that he calleth this our Island there Britaine the Great, and Ireland Britaine the Lesse. Howbeit, some of our later writers named the hither part of this Island toward the South Great, and that farther Northward the Lesse: the Inhabitants whereof in times past were distinguished into Maiatae and Caledonii, that is to say, into the inhabitants of the Champion or Plaines, and the Mountainers, as now the Scots are divided into hechtlandmen and lawlandmen. But for as much as the Romanes cared not for that farther tract, because (as Appian saith) it could not be profitable to them nor fruitfull, having set downe their bounds not farre from Edenburgh, at the first they made this hither part reduced alreadie into a Province two-fold, to wit, the Lower and the Higher, as it is gathered out of Dio. For the hither or neerer part of England, together with Wales, he termeth the Higher, the farther and Northerne part the Lower. Which thing the very seats and abiding place of the Legions in Dio do prove. The second Legion Augusta, which kept at Caerleon in Wales, and the twentieth surnamed Victrix, which remained at Chester or Deva, he placeth in the Higher Britaine, but the Sixth Legion Victrix, that was resident at Yorke, served, as he writeth, in the Lower Britaine. This division, I would suppose, was made by the Emperour Severus, because Herodian reporteth that hee after hee had vanquished Albinus, Generall of the British forces, who had usurped the Empire, and therewith reformed and set in order the State of Britain, divided the government of the Province in two parts between two Prefects or Governours.
4. After this, the Romans did set out the Province of Britaine into three parts, as is to be seen out of a manuscript of Sextus Rufus: namely, into Maxima Caesariensis, Britannia Prima, et Britannia Secunda. Which, as I take it, I have found out by the Bishops and their antient Diocesses. Lucius the Pope, in Gratian, insinuateth this much, that the Ecclesiasticall Jurisdictions of the Christians followed the Jurisdictions of the Roman Magistrates, and that Archbishops had their Seas in those cities wherein the Romane Presidents in times past made their abode. The Cities and places (saith he) in which Primats ought to sit and rule, were appointed not by the Moderne, but long before the comming of Christ, to the Primats of which cities &. the Gentils also appealed in matters of greater importance. And in those verie cities after Christs comming, the Apostles and their Successors placed Patriarks or Primats, unto whom the affaires of the Bishops and greater causes ought to be referred. Whereas, therefore, Britaine had in old time three Archbishops, to wit, of London, of Yorke, and Caerleon in Southwales, I suppose that the Province which now we call of Canterburie (for thither the Sea of London was translated) made Britannia Prima; Wales, under the Citie of Caer Leon, was Britannia Secunda; and the Province of York, which then reached unto the Limits or Borders, made Maxima Caesariensis.
5. In the age next ensuing, when the forme of the Roman Empire was daily changing, either through ambition, that more men might attaine to places of honour, or the warie forecast of the Emperours that the power of their Presidents, which grew over great, might be taken downe and abridged, they divided Britaine into five parts, to wit, Britannia Prima, Secunda, Maxima Caesariensis, Valentia, and Flavia Caesariensis. Valentia seemeth to have been the northerly part of Maxima Caesariensis, which being usurped and held by the Picts and Scots, Theodosius, Generall under Valens the Emperour, recovered out of their hands, and in honour of him named it Valentia which Marcellinus sheweth more plainely in these words: The Province now recovered, which was fallen into the enemies hands, he restored to the former state, in such sort as by his own procuring it had both a lawful governor, and was also afterwards called Valentia, at the pleasure of the Prince. Now that the sonne of this Theodosius (who being created Emperour was named Flavius Theodosius, and altered very many things in the empire) added Flavia, we may verie well conjecture, for that before the time of this Flavius we read no where of Britannia Flavia. Wherfore, to make up this matter in few words, all the south coast which one side lieth betweene the British sea and the river Thames with the Severn sea on the other side was called Britannia Prima. Britannia Secunda was that which now is Wales, Flavia Caesariensis reached from Thames to Humber. Maxima Caesariensis from the Humber to the river of Tine, or the wall of Severus. Valentia from Tine the wall or rampier [rampart] neere Edenburgh which the Scots call Gramesdike, and was the utmost limit of the Romane Empire in this Iland, when this last division was in use.
6. And now I cannot chuse but note some want of judgement in certaine men who, otherwise being verie learned, doe reckon Scotland in this account, which some of them make to have beene Maxima Caesariensis, and others Britannia Secunda, as if (forsooth) the Romans neglected not that part of the Iland, lying under a cold climate, and reckoned here those Provinces onely which they governed by Consular Lieutenants and Presidents: for Maxima Caesariensis and Valentia were ruled by Consular Lieutenants, Britannia Prima, Secunda, and Flavia by Presidents.
Now if any man would have me render a reason of this my division, and accuse me as a false bounderer and surveior, let him heare in brief what hath induced me to this opinion. Having observed thus much, that the Romans alwaies called those provinces Primas which lay nighest to Rome, as Germania Prima, Belgica Prima, Lugdunensis Prima, Aquitania Prima, Pannonia, all of which lay neerer to Rome than those that were named Secundae, and that these Primae were by the finer sort of writers termed Superiores or higher, the Secundae, Inferiores or lower, I resolved that the South-part of our Iland, and neerer to Rome, was Britannia Prima, By the same reason, seeing the Provinces Secundae (as they call them) were more remote from Rome, I supposed Wales was the Britannia Secunda. Moreover, having noted this also, that in the decaying State of their Empire those Provinces onely had Consular Magistrates which lay anent the enemies, not onely in Gaule but also in Africke, as appeareth in the Booke of Notices, also that in the said Booke Valentia with us and Maxima Caesariensis be accounted Consular Provinces, I have judged them, being next and exposed to the Scots and Picts, to lie in those places which I have spoken of. I can doe no other but ghesse that Flavia Caesariensis here was in the midst between them all, and in the verie heart of England, and so much the more confidently because that antient writer Giraldus Cambrensis is just of the same opinion with mee. And thus much of the Divisions of Britaine under the Romanes.
7. Afterwards, when the Barbarians made invasion on everie side, and civill warre daily increased among the Britans, the Iland, as bereft of all life and vigour, lay for a time languishing and forlorne, without any shew at all of government. But at length that part which inclineth to the North became two kingdomes, to wit, of the Scots and the Picts, and the Romans Pentarchie, or five portions, in this hither part became in processe of time the Heptarchie, or seven Kingdomes, of the Saxons, For they divided the whole Province of the Romans (setting Wales aside, which the remnant of Britans possessed) into seven Kingdomes, that is to say Kent, Southsex, East-England, Westsex, Northumberland, Eastsex, and Mercia.