Dragon Boat Festival in Chinese Lunar Calendar is on May 5th. It is also known as Duanyuan Festival, Noon Festival, May Festival, 5th Day Festival, Tianzhong Festival, Moxa Grass Festival, Duanwu, Double Noon, Double Five, Noon Festival, Summer Festival, and Pu Festival. It was originated from the taboo for “Vicious Day” (known as May in Chinese Lunar Calendar and was named for the epidemics of summer plaque). It is also the festival for offering sacrifice to dragons. Many customs are related to expelling and preventing plagues. At first, it was the festival for Wu-Yue Ethnic group in the downstream of Yangtze River but after Poet Qu Yuan of State of Chu committed suicide in Yangtze River, the festival became a day to commemorate Qu Yuan in China and the Chinese communities. There are a number of versions about the mysteries and poetries on Dragon Boat Festival that analyze the origin of Dragon Boat Festival:

 
Commemoration of Qu Yuan：

It was stated in Jing-Chu-Sui-Shi-Ji: “The competition held on May 5th is intended to search and rescue Qu Yuan who committed suicide in Yangtze River.” When Poet Qu Yuan of State of Chu committed suicide on Dragon Boat Festival, the people competed in boat rowing in search of his body.
 
Gou Jian Disciplining Navy：

It was recorded in Chapter 2, Er-Ying-Shui-Shi Ji of Ji-Shuan-Yuan-Hai: “The competition started from Yue King Gou Jian.” On each May 5th, when the climate turned warmer, Yue King Gou Jian disciplined the navy on this day and eventually defeated Kingdom Wu with other factors.
 
In Commemoration of Wu, Zi-Xun：

It was recorded in Jing-Chu-Shui-Shi-Ji that: “Greeting Wu on May 5th.” Wu, Zi-Xun was a loyal person but was murdered in the end. His body was discarded in the river and legend has it that he became the God of Waves. At the first of tide of Qian-Tang River estuary, people thinking of him took the boats to chase after the tidal waves in attempt to see Qu, Zi-Xun.
 
In Commemoration of Devoted Daughter, Cao Er：

It was cited from Jiawu chapter of Shi-Shuo-Xin-Yu: “Devoted Daughter Cao Er was from Shanyu. Her father was a wizard who can communicate and comfort eh divinity. On May 5th of the Second Year of HanAn, he fell into the water while greeting Wu, Zi-Xun. When the waves came up, he was drowned and his body could not be recovered.” On May 5th, Cao Er was searching for her father who accidentally fell into the water. She mourned over by the riverside for 17 days but still could not receive her father’s body, so she committed suicide by drowning herself in the river.
 
Guwu people painted dragon for worship ：

It was cited in Di-Li-Zhi-Xia, Han-Shu that: “”Yue people) often cut their hair and make tattoos on their bodies to resemble the look of son of dragon, so they would not get hurt.” As early as the late primitive society, people worshipped God of Dragon via dragon boat competition or dragon drawings between May and June in order to pray for good weather and abundant harvests.
 

Reference material：
"Myth and poetry" 1. Ancient Books Publishing House in 1956
2 East China Normal University Press, March 1997
3 Shanghai People's Publishing House, May 2006