Date of text
The year counting system is rather strange, see line 9. The symbols are (from top to bottom): ”四々八々”. That is a combination of 4 (四) and 8 (八), but with the Japanese iteration mark (々) used twice. See “Iteration Mark” for an explanation. Therefore, the combination here translates as 四々八々 = 四四八八 = 4488.
The year 4488 does not correspond to either the Japanese (nengo) or the Korean (dangi) system. For instance: in the Japanese system 1927 is Showa 2, while in the Korean system 1927 is 4260. The year 4488 seems to come from an unknown type of calendar.
Usage of hangul
The text in the document is a strange mixture of Chinese characters (used either Korean or Japanese way; Kor: hanja, Jap: kanji), Japanese characters (hirakana) and Korean characters (hangul). See the following lines for hangul:
6: (에, 하여, 7 (를, 로)
8: (하, 으니,에, 하시압)
14A: (은, 을, 에, 하시압)
14B: (에, 하여, 에는)
This is unusual in that this document is from the Japanese occupation era (before 1940), during which usually either only Chinese characters, only Japanese characters or a combination of both were used in official documents. However, during the 1920s the Japanese government tried to influence the Koreans (mainly away from Chinese influence) by promoting hangul. If this document is from that decade this could be the reason. At the same time the document also contains at least one Japanese character, the dōnojiten (iteration mark).
More background to this can be found in the lemma “Korea under Japanese rule” (Japanese policies for the Korean language):
“In the initial phase of Japanese rule, students were taught in Korean in public schools established by ethnic Korean officials who worked for the colonial government. During this time, Korean was written in a mixed Hanja–Korean script, where most lexical roots were written in Hanja and grammatical forms in Korean script. Korean textbooks from this era included excerpts from traditional Korean stories such as Heungbujeon (흥부전).
In 1921, government efforts were strengthened to promote Korean media and literature throughout Korea and also in Japan. The Japanese government also created incentives to educate ethnic Japanese students in the Korean language. As a response, the Korean Language Society was created by ethnic Koreans. In 1928, as the assimilation policy began to ramp up, the first Hangul Day (November 4) was celebrated to commemorate the Korean alphabet.
The Japanese administrative policy shifted more aggressively towards cultural assimilation in 1938 (Naisen ittai) with a new government report advising reform to strengthen the war effort. This left less room for Korean language studies and by 1943 all Korean language courses had been phased out. Although the government report advised further, more radical reform, the 10-year plan would never fully go into effect.”
Example of older types of grammar
The construct 하시압 (lines 8 and 14A) is no longer used in Korea, but only so since approx. the 1970s. It is a polite way of asking for something, like ~하세요 (spoken) or ~하십니다 (written).