By Andrei Lankov

How many people live in Korea today? The question is not particularly difficult in our era of ever-present statistics. In 2010 the population of South Korea reached 50 million.

The population of North Korea was 25.2 million at the time (when it comes to the population issue, even the notoriously secretive North Korean authorities demonstrate remarkable frankness).

But how many lived on the Korean Peninsula in the past? This question is much more difficult to answer. In “Old Korea,” the government conducted censuses, but their results were not particularly reliable, since in the past, a census was conducted with the sole purpose of locating and nailing down tax payers.

Neither individuals nor communities were particularly enthusiastic about paying taxes, so they did what they could to avoid registration. Therefore, pre-modern census results showed the strength and efficiency of the government bureaucracy, rather than the actual size of the population.

That said scholars have used other sources to compensate for the incomplete nature of official census results and have come out with some estimates of Korea’s population size in the past. They believe that around 1,000 A.D., the population of Korea was in the region of 3 million people. By the 18th century it might have reached the 7-million mark (one 10th of what it is now).

The first modern population census in Korean history was conducted by the Japanese colonial administration in 1910-11. According to its results, the population of Korea (obviously both North and South were included) was 13.1 million.

However subsequent research has demonstrated that the population was seriously underreported in that first census. Most Koreans still assumed at the time that by being registered, they would attract the attention of tax collectors and they were even less willing to pay taxes to the emperor of Japan than they had been to pay taxes to the kings of Korea.

Therefore modern scholars estimate that the actual population of Korea at the time was considerably higher ― in the region of 17 million.

The following 35 years of colonial rule was a time of dramatic increase in population. It was largely driven by an equally dramatic drop in infant mortality. In the colonial era, the average Korean woman had six children, pretty much like the average Korean women of times before.

But children stopped dying in large numbers soon after birth, due to the introduction of vaccination and some basic hygiene. As a result the average life expectancy increased from 25 years in 1910 to 44 years in 1945.

So, on the eve of liberation, the population of Korea in 1945 was 25.9 million. In the following couple of years it jumped by a few million, since many ethnic Koreans came back from Japan and China, where they had moved in the 1930s and early 1940s.

However, 1945 was not only the year of liberation, but also the year of division. At the time of division, the population ratio between North and South was 1:2. Interestingly, it has remained relatively stable in the 65 years that followed. Now, as in 1945, the population of the North is just below half that of the South.

The first few decades after liberation were marked by continued growth in the population of both Koreas. The major driving force was the fertility rate, which remained very high until the early 1960s and then began to slide very quickly. In 1960, the total fertility rate (TFR) ― the number of births per woman, was at the 6.0 level.

At that time, the Korean government began an aggressive “family planning” campaign. As a result the fertility rate was 4.5 by 1970, and by the early 1980s, it had dropped to the natural replacement level of 2.1. It did not stop at that level, though, and now the rate is one of the world’s lowest. Throughout the last decade, it was fluctuating between 1.1 and 1.2, well below the replacement level.

However this unprecedented decline did not lead to an immediate slowdown in population growth ― largely thanks to the continuous increase in life expectancy. Indeed the rate of increase in life expectancy in South Korea has been the fastest among all OECD countries.

In 2010, the average Korean male would live 76 years, while the average female would live 83 years. So, the population grew. In 1970 the population reached 30.8 million, and nowadays it is 50 million (more than 51 million if foreigners are included).

That said, the disastrously low birthrate of the present insures that we are living through the last years of population growth in South Korea. It is now expected that its population is to stabilize around 2030 and then start to decline slowly and then quickly.

This might be a problem indeed, but one should remember that merely three centuries ago the population 10 times smaller.

Professor Andrei Lankov was born in St. Petersburg, Russia, and now teaches at Kookmin University in Seoul. He can be reached at anlankov@yahoo.com.