In 1890, the average person born in the area of present-day North Korea could expect to live to 26 years old, a rate which would see only marginal change until the annexation of the Korean peninsula by the Empire of Japan in 1910. As Japanese large scale industrialization and modernization reforms would begin in the peninsula (building on the Gwangmu reforms of the previous administration), life expectancy would begin to increase rapidly as standards of living rose across the region. As a result, life expectancy would rise by twenty years between 1920 and 1940, however this growth would slow during the 1940s, as Korea lost approximately half a million people (or 2% of its population) during the Second World War. Following the war, the peninsula was split into two separate states, with the north and south each administered by the Soviet Union and the U.S. respectively (although both militaries had largely left the peninsula within a few years). In 1950, as tensions grew between the two governments regarding the legitimate rulers of the peninsula, North Korea invaded the South and set in motion the Korean War. The war would last for three years, and result in the deaths of approximately three million Koreans (with the North suffering heavier losses than the South); this caused the life expectancy in North Korea to plummet from over 49 years to less than 38 years in the first half of the 1950s.
Life expectancy in North Korea would quickly recover in the post-war years, as the Soviet Union would provide significant economic aid to the country. As a result, life expectancy would return to pre-war levels by the end of the decade and resume its steady rise until the collapse of the Soviet Union in 1991. After peaking at 70 years in the early 1990s, it is estimated that life expectancy fell by nearly seven years in the early 1990s as the country would face extreme medical and food shortages following the end of Soviet aid. U.S. estimates put the death toll of these famines at more than half a million people in the 1990s. In the past two decades, life expectancy has slowly increased once more in North Korea, returning to pre-famine levels once more in 2015, and it is now estimated that the life expectancy from birth in North Korea in 2020 is approximately 72 years old.