Polak received his first assignment in East Java and was assigned there on 7 November 1929. He departed from
Rotterdam for
Batavia on November 16 to carry out his official duties. He began serving in Bondowoso on 13 June 1930. Apart from being a civil servant, he also sat as a member of the local Regentschapsraad. Polak was then transferred to
Bojonegoro in November 1931, where he became adspirant-controleur (potential controller). He eventually became controller for land affairs in
West Kalimantan and then controller of village socio-economic affairs in
Cirebon. He was also the Cirebon residency secretary. During
World War II, Polak served at the Batavia Residency. Long before the Japanese army landed in Indonesia, Major Polak was a member of the Indische Sociaal Democratische Partij (ISDP) and
Sociaal-Democratische Arbeiderspartij (SDAP). Both accommodate social democratic groups such as Polak. During the
Japanese occupation, Polak became a Japanese prisoner of war. As an
Indo, Polak became the target of suspicion from the Kempeitai (Japanese secret police). The Japanese captured Polak and took him prisoner in
Padang. After his release, he was involved in the Japanese anti-fascist movement Eenheid door Democratie (EDD) in Cirebon. After Japan lost, he and the
romusha (Dutch and native) were treated in
Singapore. In Singapore, Polak worked at the Netherlands Bureau for Documentation and Registration of Indonesians. At the end of 1945, Polak returned to Indonesia and worked again as a colonial employee. Initially, he worked as a controller in
Jakarta until around March 1946. Polak was then involved in the establishment of the
State of East Indonesia (NIT) at the end of 1946 as translator. Since January 1947, Polak was appointed as a resident assistant attached to the council of
Balinese kings called Paruman Agung. After the
Dutch-Indonesian Round Table Conference and recognition of sovereignty on 27 December 1949, NIT disbanded. Within the NIT parliament, there are members like
Arnold Mononutu who support the Republic of Indonesia. When NIT merged into the
United States of Indonesia (RIS), NIT parliament members also entered the RIS parliament. Major Polak was among those who took part in it. == Later years ==