It was during this time, the Southern Vietnam Committee assigned him a mission of drawing the National flag. He drew a flag with red background and a five-pointed yellow star, express the idea of red blood, yellow skin; symbolizes for the nation and the solidarity of social strata. The template of the National flag by Nguyen Huu Tien was approved by the Southern Vietnam Committee and appeared for the first time in the Nam Ky Uprising 23/11/1940, then appeared in many places in Viet Minh movement (1941 – 1945).
In 1945, President Ho Chi Minh signed a decree prescribed the national flag of the Democratic Republic of Vietnam is a red background with a yellow five-pointed star as Nguyen Huu Tien designed. On 2/9/1945, the official flag with yellow star appeared in the independent declaration ceremony, President Ho Chi Minh read the Declaration of Independence at Ba Dinh Square in a historic view of thousand yellow-starred flags. On 9/5/1945, President Ho Chi Minh signed a decree fixing Vietnam's national flag is the red flag with five-pointed yellow star.
On 2/3/1946, the first Congress unanimously affirmed our country's flag is a red flag with five-pointed yellow star and also give specific provisions: a five-pointed yellow star set in the middle of a red rectangle, the width by two thirds of its length. In this meeting, Uncle Ho said: "The red flag with yellow star absorbed the blood of our compatriots in the Nam Ky Uprising 1940. The flag traveled with the Government through Asia, the flag was present all around Vietnam. So, except for 25 million Vietnamese, nobody has the right to change the national flag and national anthem."
The author's enthusiasm in creating national flag clearly portrayed in his poem:
Oh those who have red blood and yellow skin.
Let's fight under the sacred national flag
The flag’s background í the color of blood
Bright yellow star is the color of our skin
Stand up quickly, the country is calling our names
Dear officers, farmers, workers, businessmen, soldiers.
United as the five-pointed yellow star.
How about Nguyen Huu Tien? The man who drew the National flag was arrested and executed by firing squad on 28-8-1941 in Hoc Mon, on the same day with other Nam Ky Uprising soldiers including Nguyen Thi Minh Khai, Vo Van Tan, Ha Huy Tap .. .
Also at the first Congress, together with the National Flag, the Congress also agreed to take the song “Tien quan ca” of Van Cao as the official anthem. According to the musician Van Cao, “Tien quan ca” was completed by the end of October 1944. Writer Vu Bang recalled in an article: "... 19/8 was the Uprising day in the whole the country, from rural to urban, from alley to alley, people were singing "Tien quan ca" and "Diet phat xit” (Killing fascists).
Before composing “Tien quan ca”, Van Cao wrote patriotic songs such as Dong Da, Thang Long hanh khuc ca. Enlightenment by the revolution, he focused on composing many songs encouraging people to fight for freedom. “Tien quan ca” was written in the narrow attic of house number 45 Nguyen Thuong Hien Street (Hanoi) by the end of 1944. It was also pre-uprising period, the revolutionary spirit was seething. The news of Vo Nhai victory spread to Hanoi elated social strata. Later, Van Cao recalled: "Right in front of my eyes, the gray sky and groves of Hanoi was no longer there. I am living in a certain forest up there, in Viet Bac. There are many clouds and much hope. And the song is done... ".
The musician continued: "The national anthem is the formation of many years of experience and concern for a long time. When writing it, I was just thinking about how to meet the public needs, how to make it catchy, easy to remember. November 1944, in the attic of Mr. Van Lang’s house in Bat Trang village, a secret address at the time of the revolution, I wrote the song “Tien quan ca” which was print on the first musical page of the Independence News..."
On 7/8/1945, a large rally was held at the Opera House Square, the choir of the Young Pioneers sang the “Tien quan ca” song, saluted the yellow-starred red flag. Van Cao remembers that he cried when the big red flag with yellow star was released from the balcony of the Opera House while the song “Tien quan ca” was sang...
Nearly twenty years have passed, the song has amended a couple of letters, but it is basically still the “Tien quan ca” which was agreed by the first Congress as the National anthem. The anthem with the national flag, the yellow star - red flag, is a beautiful and unforgettable symbol to the people of Vietnam.
