John Overton (1640-1713) was the son of a bookseller Henry Overton and married the daughter of the publisher William Garrett. He was a printseller who in 1665 acquired the stock of Peter Stent who died of the plague that year and who had arguably the largest collection of prints on the market at the time. Amongst this stock he found twelve copper plates of the English counties by William Smith. These formed the nucleus of a set of maps of the English Counties. After the disastrous Fire of London in 1666, he began the process of building a set of engraved plates of the English counties. Overton commissioned the engraving of some new plates for missing counties; amongst them is one of Somerset drawn from that of John Speed by an unknown engraver. It was first advertised in Overton’s catalogue in 1667 despite being dated 1668 in the imprint. This bears signs of alteration but no known example survives of an earlier state. Overton did change addresses around this time.

Those counties which Overton could not provide from his own stock were supplied by the acquired maps of Speed, Blaeu or Jansson. These county atlases were an English version of a rich seam of similar Dutch composite atlases published from the mid-seventeenth century. They are exceedingly rare surviving in just four known examples. Hodson (1984-97) I p. 61; Needell (1995) 81; Skelton (1970) 89.