Gerhard D. Wempe opened a clock and watch shop in Elsfleth on the Weser in 1878. The family business grew into a major watch and jewellery retailer. In 1907, Wempe opened a shop in Altona; its headquarters have been in Hamburg since 1923. The company took an important step toward watchmaking in 1938, when Herbert Wempe acquired the Chronometer-Werke Hamburg, founded in 1905. Under the name Wempe Chronometerwerke, the company produced precision chronometers, including instruments for maritime use. During the Second World War, the operation was considered essential to the war effort; prisoners of war were also employed there. In 2000, the Wempe family contributed to a fund to compensate former forced labourers. In 2005, Wempe acquired and renovated the observatory in Glashütte, establishing a chronometer testing centre and a watchmaking facility there. Since 2006, the company has made its own wristwatches in Glashütte under the Wempe Chronometerwerke and Wempe Zeitmeister lines. Wempe's history thus links the watch trade in Hamburg with chronometer production and today's watch manufacture in Glashütte.