She was born Johanna Tumbuan in Amurang, in the region of Minahasa in North Sulawesi.
[1] In addition, Johanna also witnessed the Proclamation of Indonesian Independence that was announced by Sukarno and Mohammad Hatta on 17 August 1945.
She continued her studies in the United States and Britain after her husband, Masdani, died in October 1967.
[1] Johanna Tumbuan Masdani died on 13 May 2006 and was buried in Kalibata Heroes' Cemetery on 15 May 2006.
[1] Johanna Masdani was acknowledged by the Indonesian government several times through the conferring of several honors:[4]