There were many complications in the history of designation of Han-geul Day on 9th October as today. Since King Sejong performed the project of inventing Han-geul secretly, there is no evident record related to the invention of Han-geul even in the authentic history. Although it is common to record the events connected with kings with exact dates, the record related to invention of Han-geul is not seen at all in the authentic history until the end of December of 1443(King Sejong 25). It just says without the date that 'the king invented 28 Un Mun() this month'.

 And then after 3 years, at the end of September 1446(King Sejong 28), the record 'Hoon Min Jung Um(ƹ) was completed this month' is seen without the date, either. These two records confused contemporary scholars a bit. So, they interpreted that Han-geul was first invented in December of 1443 but it was completed in September of 1446 after 3 years of modification and supplement. Thus they thought it would be better to take the invention time of Han-geul September 1446 rather than December 1443. Since the exact date of September was not recorded in the authentic history however, they just assumed the last day of the month and fixed Han-geul Day on 29th of October by converting it into solar calendar.

   In 1940's, Bang Jong Hyun() pointed out the record of September 1446 should be interpreted as meaning completion of the book {Hoon Min Jung Um(ƹ)} (so called HaeRyeBon(طʺ)) rather than completion of Han-geul itself as letters. Being embarrassed, the scholars who misinterpreted the record of September 1446 made an excuse that the designation of Han-geul Day was not totally wrong because Hoon Min Jung Um was promulgated in September 1446.

 Thereupon Han-geul Day had been maintained on 29th of October. However, the assertion that Hoon Min Jung Um was promulgated in September 1446 is also groundless. The record of September 1446 is about reporting the completion of a manuscript of HaeRyeBon(طʺ) to King Sejong. It usually took several months for the books to be published and granted to the vassals even after a manuscript was completed. Consequently, Hoon Min Jung Um could never have been promulgated in September 1446.

Even though there are some places in which hang the picture 'the promulgation of Hoon Min Jung Um' on the wall, there is no record of any official events of promulgation of Hoon Min Jung Um by King Sejong. In short, designation of Han-geul Day on 29th of October stemmed from misinterpretation of historical records.

The original copy of Hoon Min Jung Um HaeRyeBon(ƹ طʺ) was found afterwards. The date is written as 'the first part of September in the 28th year of King Sejong' in the preface by Jung In Ji. Although it was not the exact date either, it provided them with the necessity to shift approximately 20 days ahead from the last day of September. Therefore, Han-geul Day was fixed on the 9th of October moving 20 days ahead from 29th of October.

Although there were a lot of meanderings and happenings in the process of designation of Han-geul Day, it is true that all Korean people need a commemoration day to remember the intention of King Sejong and the scientific excellence of Han-geul. It is said that a linguist in the United States throw a party every year to commemorate the day on which the greatest character in the world was invented. Not only on Han-geul Day, but sometimes we need to be grateful to Han-geul for allowing us to live more comfortable lives.