[2] Yukjin speakers currently live not only in the Tumen River homeland, now part of North Korea, but also in the Korean diaspora in Northeast China and Central Asia that formed in the nineteenth and twentieth centuries.
The Sino-Korean term 六鎭 ryukchin 'six garrisons' refers to the six towns of Hoeryŏng, Chongsŏng, Onsŏng, Kyŏngwŏn, Kyŏnghŭng, and Puryŏng, all located south of a bend of the Tumen River.
The area of these towns belonged to the Tungusic-speaking Jurchen people until the early fifteenth century, when King Sejong conquered the area into Korea's Hamgyong Province and peopled the six towns with immigrants from southeastern Korea.
[5] Some analyses consider the language of Kyŏnghŭng and Puryŏng to belong to the mainstream Hamgyong dialect rather than to Yukjin.
[9] In response to poor harvests in the 1860s, Yukjin speakers began emigrating to the southern part of Primorsky Krai in the Russian Far East.
[12] Larger waves of immigrants from other parts of North Hamgyŏng arrived in the area in the 1910s and 1920s, fleeing the Japanese annexation of Korea.
[13] In the 1930s, Stalin ordered the forced resettlement of the entire Korean population of the Russian Far East, some 250,000 people.
[24] This vowel represents an intermediate stage in a diachronic sound shift from uy [ɨj] > [ï] > i [i].
[5] Most analyses of the verbal paradigm identify three speech levels of formality and politeness, which are distinguished by sentence-final suffixes.
[47] Mood-marking sentence-final suffixes which have been identified by Chinese, Korean, and Western researchers include:[d] Highly unusually, the Yukjin negative particle (such as ani 'not', mwo(s) 'cannot') intervenes between the main verb and the auxiliary, unlike in other Koreanic varieties (except other Hamgyŏng varieties) where the particle either precedes the main verb or follows the auxiliary.
[60][61] 빨리ppalliquickly나namove.out모mwocannot오디wo-ticome-DEC빨리 나 모 오디ppalli na mwo wo-tiquickly move.out cannot come-DEC'[I] can't come out quickly'빨리ppalliquickly못mwoscannot나오지na-wo-cimove.out-come-DEC빨리 못 나오지ppalli mwos na-wo-ciquickly cannot move.out-come-DEC'[I] can't come out quickly'When followed by the verb kath- 'to be like', the normally adnominal verbal suffixes -n and -l function as nominalizers.
The basic Yukjin lexicon is unusually archaic, preserving many forms attested in Middle Korean but since lost in other dialects.
This includes[d] the verb stem 가리우 kaliwu- 'to breed an animal', from the Manchu verb stem gari- 'to copulate [for dogs]' with the Koreanic causative suffix -wu attached; 우쿠리 wukwuli 'wicker basket' from Manchu uku 'id.