How is the national electoral register created?

Korea, NEC, Public Official Election Act (as amended in 26 July 2017) [the text of the new bill passed on 27 December 2020 is not available online], accessed 10 April 2020

Article 37 (Preparation of Electoral Register)

National Election Commission, Preparation of Voter Lists [web content], accessed 10 April 2020

“Whenever an election is held, the head of the relevant Gu/Si/Gun prepares a voters lists for each precinct based on the resident register (Korean citizens) and register for domestic residence (non-Korean citizens, only used in local elections) as a computerized database.”