Sam-il Movement Day is a public holiday to commemorate the independence movement against the Japanese colonialism that started on 1 March 1919, when 33 nationalists affirmed the following Korean Declaration of Independence, that was composed some time earlier by historian Choi Namseon and poet Manhae:
"We herewith proclaim the independence of Korea and the liberty of the Korean people. We tell it to the world in witness of the equality of all nations and we pass it on to our posterity as their inherent right. We make this proclamation, having back of us 5,000 year of history, and 20,000,000 of a united loyal people. We take this step to insure to our children for all time to come, personal liberty in accord with the awakening consciousness of this new era. This is the clear leading of God, the moving principle of the present age, the whole human race's just claim. It is something that cannot be stamped out, or stifled, or gagged, or suppressed by any means."
The Sam-il Movement is considered the first national non-violent protest. Like Martin Luther King Jr. and Mahatma Ghandi’s pacifistic (non-violent) protests, so too the Samil Movement involved non-violent protest – but just at a much larger scale. By the end of the movement, an estimated 2 000 000 protesters participated. Thousands of Koreans died during these protests.
In Taekwon-Do, one of the 3rd Dan patterns is named after this movement. Sam-il Teul has 33 movements in honour of the 33 nationalists that started the movement.