German diplomat and art collector. Martin Johann Rücker Freiherr von Jenisch was the third child of Alfred Rücker, a Hamburg senator and former Hanseatic Minister Resident at the Court of St James in London, and his wife Olga Adelaide, née d’Araujo Abreâ (1840–1890). Rücker-Jenisch studied law in Bonn and Berlin. After completing his studies and working in the Ministry of Justice, he entered the diplomatic service, where he was to hold various positions at the German embassies in Washington (1886–1887), Vienna (1889), Buenos Aires (1890), London (1891–1897), and Brussels (1898–1900), among others.
On 1 January 1903, Rücker-Jenisch was appointed Consul General in Cairo, where he remained until 1906. During this time, he supported the excavations undertaken by the Deutsche Orient-Gesellschaft (German Oriental Society) in Egypt. With the help of Egyptologist Ludwig Borchardt (1863–1938), Jenisch acquired a considerable collection of Egyptian art. He bequeathed most of it to the Museum für Völkerkunde (now MARKK. Museum am Rothenbaum. Kulturen und Künste der Welt) in Hamburg, thereby laying the foundation for its ancient Egyptian collection. Furthermore, he donated several late antique and Islamic artifacts to the Ancient Christian Department of the Kaiser-Friedrich-Museum (now the Bode Museum) in Berlin (textiles) and the Museum für Kunst und Gewerbe Hamburg (stucco and glass windows, see IG_493–496).