This terrestrial map by Gerard Mercator is believed to be the earliest to focus more on the region of northwestern France, surprisingly predating Abraham Ortelius whose own map of the region was not published until 1595. However, it is generally accepted that as the two were close friends, and that Mercator held off publishing his regional maps so that Ortelius could publish his ‘Theatrum Orbis Terrarum’ first. This implies that the Mercator maps were advanced by 1570, when the first edition of Ortelius’ work was published. In 1578 he claimed that he had prepared those for France, the Low Countries, and Germany. It seems though that the delay was due to a lack of engravers. Several even earlier maps were published in Italy which are generally referred to as part of the Lafreri school. However, none were more focused than the whole of France and none advanced the detail of the Channel Islands.Gerard Mercator (1512-94), the inventor of the projection named after him, began in 1585 to produce a series of ‘Tabulae Geographicae’ of differing European countries. This culminated in 1595 in the ‘Atlas Sive Cosmographicae’, the first use of the term ‘Atlas’. It contained 107 maps of the world. The birth of the modern atlas as we know it is not quite so simple. The first collections of maps representing the world were put together in Italy and are loosely called Lafreri atlases after their main proponent Antonio Lafreri. However, these contained maps by various cartographers and therefore were in different styles and sizes, the maps usually bear large, attached margins to make them uniform. In 1570 Abraham Ortelius published the ‘Theatrum Orbis Terrarum’, the first collection of maps with a uniform size and style. It was an immediate success. Mercator is one of the giants in the history of cartography; it is he who began the scientific study of the subject. His talents were recognised at the time by Ortelius who called him the ‘Ptolemy of our time’. Born near Antwerp. He studied mathematics at the University of Leuven under Gemma Frisius. The map extends eastwards towards Picardy and south to the River Gironde. According to the text setting on the verso, this map of Brittany and Normandy is from the first edition of the ‘Tabulae Geographicae Galliae, Belgii Inferioris & Germaniae’, published in 1585. Additional manuscript contemporary notations refer to events immediately following publication. The latest date refers to the Battle of Ivry in Normandy on 14 March 1590. The Channel Islands are displayed more accurately than any previous map, especially in their placement and proportions. They bear no relation to Lucas Jansz. Waghenaer’s sea chart of 1583. Provenance: private Jersey collection. Karrow (1993) 56/68; Keuning (1947); Van der Krogt (1997-2010) 4001:1; Koeman (1967-70) Me 9 (2); Watelet (1994).