The partnership of Jean Covens and Corneille Mortier was founded in 1721 by the two brothers-in-law. It was built on the business of Corneille’s father Pierre Mortier who began in 1685. The firm through their descendants would survive until 1866. A fine large scale map of the region of Hannover extending from Hamburg prominently displayed in the north, to Cassel, Munden and Gottingem in the south. The regions capital Hannover is central with other cities such as Luneberg, Brunswick, Wolfenbuttel, Magdeburg, Hildesheim and Bremen all prominently displayed in red.