Starting with the 1 Pf. in 1960, followed by the 10 Pf. in 1963, and the 5 Pf. in 1968, the old style coins were gradually replaced with new coins depicting the state name "Deutsche Demokratische Republik." Aluminium 1 Mark, 2 Mark and 50 Pfennig pieces were released for circulation in 1956, 1957 and 1958, respectively. In 1969, brass 20 Pfennig coins were introduced, with nickel-bronze (later cupro-nickel) 5 Mark coins issued from 1968. In 1973 and 1974, 1 and 2 Mark coins were redesigned dropping the former "Deutsche Mark" title. The brass 20 Pfennig coins were issued partly because pay telephones had a standard charge of 20 Pf. and were having problems with smaller aluminium coins jamming due to their light weight. Commemorative 5, 10, and 20 Mark coins of various types have also occasionally made it into circulation.
The Supreme Council of the 1919 Paris Peace Conference awarded all of German East Africa (GEA) to Britain on 7 May 1919, over the strenuous objections of Belgium.  : 240 The British colonial secretary , Alfred Milner , and Belgium's minister plenipotentiary to the conference, Pierre Orts , then negotiated the Anglo-Belgian agreement of 30 May 1919  : 618–9 where Britain ceded the north-western GEA provinces of Ruanda and Urundi to Belgium.  : 246 The conference's Commission on Mandates ratified this agreement on 16 July 1919.  : 246–7 The Supreme Council accepted the agreement on 7 August 1919.  : 612–3