The flag of Lithuania consists of a horizontal tricolour of yellow, green and red. It was adopted on March 20, 1989, almost two years before the reestablishment of Lithuania's independence following the end of the Soviet Union. Before its readoption, the flag had been used from 1918 until 1940 while Lithuania was occupied and then annexed by the Soviet Union. This flag had lighter colours. After a brief occupation by Nazi Germany (1941-1945), from 1945 until 1989, the Soviet Lithuanian flag consisted first of a generic red Soviet flag with the name of the republic, then changed to the red flag with white and green bars at the bottom. The last alteration to the current flag occurred in 2004 when the aspect ratio changed from 1:2 to 3:5.
Passed on June 26, 1991, the Law of the Republic of Lithuania on the Lithuanian State Flag governs the design, sizes and use of the state flag. The law was last amended on July 8, 2004, with the most notable changes including the switching of the national flag ratio from 1:2 to 3:5 and the official adoption of a historical flag as the state (government) flag. The amendment came into force on September 1, 2004, after it was approved by President Valdas Adamkus.
The proper colours of both the national and state flag are made according to the Pantone Matching System, specifically Pantone textile-paper (TP). The ratio of both the national and state flag must be 3:5, with the standard flag size to be 1 meter by 1.7 meters. Different sizes of the flag can be created, but they must conform to the colour codes and ratio requirements set in the law.
The yellow in the flag is meant to symbolise the golden fields of Lithuania, the green is for its green countrysides, and the red represents all the blood that has been shed for Lithuania.