Northeastern Vietnamese

Northeastern Vietnamese (Vietnamese: 方語東北, Bin'am: Fïëng Ngḯh Dong Bák), sometimes referred to as Dieu (㗂趙; Śiéng Dieu) or Dieuese Vietnamese, is the variety of spoken in Daidieu. Nearly 100% of the population of Daidieu speaks Northeastern Vietnamese natively.

Although it is also spoken by the, it differs from other varieties spoken in , particularly in the writing system and to a lesser extent, phonology. Northeastern Vietnamese pronounciations were standarized by the Kingdom of Vietnam in the late 1940s and 1950s in dictionaries and are more conservative than other varieties. Written Vietnamese in Daidieu continues to use (Chinese characters) and  in contrast to Vietnam, where the  (chữ Quốc ngữ) is used. Despite this, Northeastern Vietnamese and other varieties remain mutually intelligible with each other.

History
Northeastern Vietnamese emerged as a separate dialect from other dialects of Vietnamese in the late 1940s. Prior to the standarization of Northeastern Vietnamese as a dialect, the North, North-Central, and Central Vietnamese dialects were mainly spoken.

Cúk Hiạ́w, other members of the PIV, and several linguists advocated for a "hyper-Sinicization" of Vietnamese in order to purge any colonial influences. Some of those reforms included eliminating all French loanwords, and reviving the use of Chữ Nôm to write Vietnamese. In 1948, the Rime Dictionary of the Vietnamese Language (韻書㗂越) was published. It standarized the pronounciations of Vietnamese and it was inspired by. The pronounciations were derived from Northern, North-Central, and Central Vietnamese.

After the end of the, Northeastern Vietnamese quickly spread across all classes of society since the government of Daidieu banned the use of the Latin script and textbooks were massively published by the government.

Phonology
The phonology of Northeastern Vietnamese tends to be more conservative than other dialects. It was standarized in the Rime Dictionary of the Vietnamese Language

Consonants

 * {| class=wikitable style=text-align:center

! colspan=2| ! Labial ! Dental/ Alveolar ! Retroflex ! Palatal ! Velar ! Glottal ! colspan=2| Nasal ! rowspan=3| Stop ! tenuis ! aspirated ! implosive ! rowspan=2| Fricative ! voiceless ! voiced ! colspan=2| Approximant ! colspan=2| Rhotic
 * (m)
 * (n)
 * (ny)
 * (ng)
 * (ng)
 * (p)
 * (t)
 * (ṭ)
 * (c)
 * (k)
 * (th)
 * (kh)
 * (kh)
 * (kh)
 * (kh)
 * (b)
 * (d)
 * (f)
 * (s)
 * (ṣ)
 * (v)
 * (z)
 * (g)
 * (g)
 * (g)
 * (l)
 * (y)
 * (w)
 * (y)
 * (w)
 * colspan=2| (r)
 * }
 * }
 * }
 * }
 * }

Comparison with other Vietnamese dialects
This uses the Vietnamese alphabet for consistency.
 * s is pronounced /ʂ/, like in all dialects except for Hanoi, which pronounces it as /s/.
 * ch is pronounced /c/, like in all dialects except for Hanoi, where it is merged with tr to become /tɕ/.
 * tr is pronounced /ʈ/, like in all dialects except for Hanoi, wheee it is merged with ch to become /tɕ/
 * Northeastern Vietnamese retains a 3-way distinction between d /z/, gi /j/, and r /r/. Those have merged into /z/ in Northern Vietnamese, while southern dialects pronounce r as /r/ and d and gi as /j/.
 * kh is pronounced /kʰ/, unlike other dialects, which pronounce it as /x/.

Chữ Nôm
One of the main differences between Written Northeastern Vietnamese and other Vietnamese dialects is the use of Chinese characters (chữ Hán). Although the use of the Vietnamese alphabet had been commonplace in Daidieu since the 1920s, Dieuese independence activists and nationalists, such as Cúk Hiạ́w and Lý Văn Trụng, heavily protested the use of the alphabet as it was seen as a symbol of French colonialism. Following the Kingdom of Vietnam's independence in 1946, reforms to the Northeastern Vietnamese dialect began. In 1950, a ban on chữ Quốc ngữ was declared by Cúk Hiạ́w (it would not be lifted until 1995), and Chữ Nôm became the official writing system of Daidieu, where it remains in use today.

Vietnamese alphabet
During the period of the People's Republic of Daidieu (1972-1979), Supreme Leader Kim Nau Szi re-introduced the Vietnamese alphabet in schools, with the hopes of unifying Northeastern Vietnamese with the other Vietnamese dialects. However, as relations between Vietnam and Daidieu grew increasingly cold, the government ended the introduction of Chữ Quốc ngữ by at least 1976. In 1977, the Bíng Ëm romanization system was created to replace the use of the Vietnamese alphabet as the official romanization scheme, and is still the official scheme today.

Today, the Vietnamese alphabet is rarely used in Daidieu except as abbreviations when dealing with rare characters or characters with a high amount of strokes. Many Dieuese and Vietnamese living near the Daidieu-Vietnam border often understand both Chữ Nôm and Chữ Quốc ngữ.