Born into an aristocratic Javanese family in the Dutch East Indies, now Indonesia, she attended a Dutch language primary school.
Her grandfather, Pangeran Ario Tjondronegoro IV, became a Regency Chief at the age of 25, while Kartini's older brother Sosrokartono was an accomplished linguist.
After she turned 12 she was secluded (pingit) at home, a common practice among Javanese nobility, to prepare young girls for their marriage. In her letters, Raden Adjeng Kartini wrote about her views of the social conditions prevailing at that time, particularly the condition of native Indonesian women.
During seclusion girls were not allowed to leave their parents' house until they were married, at which point authority over them was transferred to their husbands. According to the late Sulastin Sutrisno, the Dutch Government has been unable to track down J. Most of her letters protest the Javanese cultural tendency to impose obstacles on women's development. Kartini wrote of her ideas and ambitions, including Zelf-ontwikkeling, Zelf-onderricht, Zelf-vertrouwen, Zelf-werkzaamheid and Solidariteit.
At this time, polygamy was a common practice among the nobility. Colonial regulations required a Regency Chief to marry a member of the nobility.
Since Ngasirah was not of sufficiently high nobility, her father married a second time to Woerjan (Moerjam), a direct descendant of the Raja of Madura.
Kartini's father, Sosroningrat, became Regency Chief of Jepara.