Mon National Day (Mon: တ္ၚဲကောန်ဂကူမန်listen^ⓘ, rungmoam kaun kay kaw mon; Burmese: မွန်အမျိုးသားနေ့; Thai: วันชาติมอญ) is an annual national day that commemorates the founding of Hanthawaddy kingdom.^[1] Mon National Day is celebrated by the Mon people in Myanmar and Thailand, and by overseas Mon communities.^[1] The day is held on the first waning day of the lunar month of Tabodwe (Maik in Mon) in the Burmese calendar, following Māgha Pūjā.^[2]

Mon National Day was first celebrated in 1947, marking the mythic foundation of last Mon kingdom, Hanthawaddy (now centred in Bago), in CE 573.^[3][4] The origins of Mon National Day parallel that of Karen New Year, as both were colonial-era celebrations that fostered the ethnic identity of these communities.^[3] The former was established by the United Mon Association via resolution, in October 1947 in the village of Kamawuk in Mudon Township.^[5]

In 1974, the Burma Socialist Programme Party-led government officially recognized Mon State Day on 19 March, to celebrate the establishment of Mon State.^[3]

Mon National Day is currently not recognized by the Burmese national government as a national holiday. However, in 2013, the Mon State Government expressed interest in organizing celebrations for the holiday.^[6] That same year, Aung San Suu Kyi, the country's de facto leader, spoke at large-scale Mon National Day celebrations held at Yangon's People's Square and Park.^[7] In 2016, activists and festivity organizers petitioned the national government to observe Mon National Day as a public holiday.^[8][9] Since 2017, the Mon State Government has earmarked funding for state-wide Mon National Day celebrations.^[10] In 2018, Mon and Kayin State Governments jointly earmarked funding for inaugural Mon National Day celebrations in Kayin State.^[11]

Mon National Day is celebrated by Mon communities throughout Myanmar, primarily in Mon and Kayin States, Yangon and Taninthayi Regions.^[12] Mon National Day in Thailand was first held in Bangkok in 1982.^{[citation needed]} Countries with significant Mon populations, including in Singapore, Malaysia, South Korea, also observe the occasion.^[12]

Mon National Day is marked with literature competitions, photo exhibitions, traditional boxing competitions, and traditional songs and dances performed by a popular Mon drama troupes and other cultural shows.^[13][14] Traditional Mon musical instruments, food and handicrafts are also sold during festivities.^[13] During the festivities, many celebrants don traditional Mon outfits, consisting of red-colored longyis and white tops.^[15]