History of Singapore
During World War 2, Singapore was conquered and occupied by the Japanese Empire from 1942 to 1945. When the war ended, Singapore reverted to British control, with increasing levels of self-government being granted, culminating in Singapore's merger with the Federation of Malaya to form Malaysia in 1963. However, social unrest and disputes between Singapore's ruling People's Action Party and Malaysia's Alliance Party resulted in Singapore's expulsion from Malaysia. Singapore became an independent republic on 9 August 1965.
Singapore passport
The first version of the modern Singapore passport was introduced on 20 June 1966, replacing the Singapore Provisional Passport issued from 17 August 1965. Between 1963 and 1965, Malaysian passports were issued to residents of Singapore (when it formed part of Malaysia) and colonial British passports were issued prior to 1963. The Straits Settlements, of which Singapore was its capital from 1832 until 1946, also issued its own passports prior to World War II.