[6] The Joseon Kingdom later attempted a standardization of length based on square brass rulers, which were used by magistrates and the secret police to fight commercial fraud.
[1] The 1897 Law on Weights and Measures uniting Korea's various local systems was the first legislation enacted upon the Joseon's establishment of the Korean Empire.
[8] The metrication was not applied to imported or exported goods[11] and remained so generally spotty as to be considered a failure,[9] with the government abandoning its attempts to enforce the statute by 1970.
[8] The traditional units feature in many Korean sayings[a] and much of its literature and poetry, including the national anthem, which mentions Korea's "three thousand lis of rivers and mountains".
"[8] Nonetheless, strong opposition from the construction and jewelry industries and negative media coverage forced Korean politicians to avoid the topic and regulators to settle for dual use of conventional and metric measures.
[8] A 2006 study found 88% of real estate companies and 71% of jewelers in 7 major markets were still using the pyeong and don,[9] after which the government decided simply to criminalize further commercial use of traditional units.
)[17] The sale of rulers marking Korean feet was ended[8] and a Measure Act effective 1 July 2007 empowered the Korean Agency for Technology and Standards[13] of the Ministry of Commerce to begin immediately levying fines of up to ₩500,000 for commercial use of the pyeong and don, with less common units enjoying a longer grace period.
[9] The ban also included use of American units, such as describing the display size of televisions and computer monitors in terms of inches.
Despite the importance of the Soviet Union in establishing North Korea, Kim Il Sung continued official use of Korean units until the DPRK's notional metrication under National Standard 4077–75 on 14 April 1975.
[19][c] It joined the Meter Treaty in 1982[10] or 1989,[20] although it was removed from the International Bureau for Weights and Measures and related organizations in 2012 for its years of failure to pay the necessary fees.
[26] North Korea uses the pyeong in various regulations, such as the 50 py per person allowed for private farming in 1987,[27] despite guides who disparage the unit as a historical relic of the South to foreign tourists visiting the country.
[28] The metric system is thought not to have spread to domestic factories or stores prior to Kim Jong Un's metrification initiative, announced in May 2013.
[22] His announcement in the state-run quarterly Cultural Language Study said that increasing use of the metric system would "strengthen international exchange and cooperation... in the fields of industry, science, and technology and even in the area of general social life".
[4] The Korean li previously bore values around 434.16 m (3rd century), 531.18 m (6th–7th), 559.8 m (7th–10th), 552.96 m (10th–14th),[30] and 450 m (19th);[31] it was also reckoned based on travel time and therefore varied in length between the plains and mountains.
[36] Farms and large estates were formerly generally measured in majigi, which is notionally not based on multiples of the pyeong but on the amount of land suitable for the planting of one mall of rice or grain seed.