Sing Rattanasamai joined the Lao Issara independence movement and later was appointed as the original Lao Issara defense minister by Prince Phetsarath,  the 1st Prime Minister of Luang Phrabang in French Laos from August  21, 1941, to October  10, 1945.
In October 1945, Sing joined the Lao Issara independence movement; he was given command of the civil guard in Vientiane. He was subsequently appointed as the original Lao Issara defense minister by Prince Phetsarath. Prince Phetsarath Ratanavongsa (Somdej Chao Maha Uparaja Petsaraj Ratanavongsa (Lao:     ) (19 January 1890  14 October 1959) was the 1st Prime Minister of Luang Phrabang in French Laos from 21 August 1941 to 10 October 1945, and Head of State of Laos between 12 October 1945 and 4 April 1946. 
