Foxe here elaborates briefly on several important and implied parallels between the Christian conversion of the British Isles and the contemporary experience of reformation. The conversion had occurred through the activity of preachers ('through whose ministery this realm & ileland of Britain was eftsones reduced to the faith & law of the Lord'. The British Isles were Christianised whilst the Roman emperors were still heathens. Foxe weaves in a prophecy from Isaiah ch. 42 and the passage is loosely based on Henry Huntingdon's Chronicle (T. Arnold, ed. Henry of Huntingdon. Henrici Huntendunensis Historia Anglorum, the History of the English, by Henry, Archdeacon of Huntingdon, from B. C. 55 to A. D. 1154 [London: Rolls Series, 1879], ch. 1, pp. 27-8). For the narrative of the death of King Lucius and events thereafter, Foxe relied on Matthew Paris' Flores Historiarum, which had been published in 1567 (H. R. Luard, ed. Matthew Paris. Flores Historiarum 3 vols [London: Rolls Series, 1890], 1, p. 149) and also on the Magdeburg Centuries, II, ch. 2, p. 9.

This is the first in a series of tables running through the early books of Foxe's martyrology from the 1570 edition onwards, laying out the English regnal succession. Here Foxe provides that for the early British kingship. Foxe constructed it independently, and from a number of sources. It is a good example of his collating and critical skills. He certainly used Ranulph Higden's Polychronicon (J. R. Lumby, ed. Polychronicon Ranulphi Higden monachi Cestrensis: together with the English translations of John Trevisa and of an unknown writer of the fifteenth century [London: Rolls Series, 1879], book 4, ch.19-book 5, ch. 4) as well as Bede book 1. Geoffrey of Monmouth (ch. 79) might have been drawn on indirectly (through John Bale's Catalogus or the English Votaries, or even from Fabian's Chronicles (R. Fabyan, The Chronicle of Fabian [London, 1559], preface: table 3). He would almost certainly have consulted one of the editions of the sixteenth-century Breviat chronicles, with their lists of British King, and may even have worked with John Stow whilst he was preparing his A Summary of English Chronicles (London, 1565), which furnishes a similar genealogy, albeit Foxe here provides some telling additional details. Information may have also been taken from Henry Huntingdon's Chronicle (T. Arnold, ed. Henry of Huntingdon. Henrici Huntendunensis Historia Anglorum, the History of the English, by Henry, Archdeacon of Huntingdon, from B. C. 55 to A. D. 1154 [London: Rolls Series, 1879], book 8 ch. 8, pp. 575-77). The evidence suggests that Foxe prepared this material independently, and made up his own mind on the various issues relating to the sensitive issues of chronology which the table contains.

Foxe's account of the Roman government of Constantine in Britain and the eventual retreat of Rome from the British Isles made the important point, from Foxe's point of view, that it was religious persecution, rather than Christianity, which had been imported from Rome. He could have taken his material from a number of sources. He seems to have used Fabian's Chronicle as his base-text (R. Fabyan, The Chronicle of Fabian [London, 1559], book 5, chs 68-75) for most of the passage, although the brief reference to the rise of persecution in the British Isles under Diocletian seems most closely to correspond to Henry Huntingdon's Chronicle (T. Arnold, ed. Henry of Huntingdon. Henrici Huntendunensis Historia Anglorum, the History of the English, by Henry, Archdeacon of Huntingdon, from B. C. 55 to A. D. 1154 [London: Rolls Series, 1879], book 1, ch. 36). The source for the two Latin citations from Gildas at the end of the passage represents something of a puzzle. Neither of them appear in Fabian's Chronicle. The first one could have come from one of a number of sources, though the Joscelyn edition of Gildas, published in 1567, includes it in a version which accords most nearly to the form it appears in Foxe's text. The second quotation does not appear, however, in the Joscelyn edition - indeed it does not appear in Gildas at all, or in any of the sources Foxe habitually used. Its appearance here is something of a mystery.