Burma is the largest country by geographical area in Indo-China ( mainland of South East Asia ) , situated on the north-west of Thailand and facing the Bay of Benggal to the south-west with the Andaman Sea defining its southern periphery. Starting in 1854, Burma used the stamps of British India without any form of overprinting. The 1st stamps of Burma were stamps of British India overprinted the word " Burma " from 1st April 1937. Between 1942 till 1945, stamps with Japanese postmarks were issued in Burma. After the war, postal services were restricted under Briitsh administration and stamps were overprinted with MILY ADMIN. On 4th. January 1948, Burma became an independent republic as the Union of Burma and stamps were issued with that name until 1973. From 1974, stamps were marked with Socialist Republic of the Union of Burma and in 1990 as Union of Myanmar.