As of 2006, the population of the Republic of Korea stood at 49,024,737. In terms of density, there are roughly 480 people per square kilometer. Conversely, the population of North Korea was 24,000,000 in 2005. Once considered to be a serious social problem, historically, the threat of rapid population growth posed serious social repercussions on developing countries.
Yet such fears of swelling growth hardly raise much cause for alarm on the peninsula. With the advent of successful family

planning campaigns and changing attitudes, there are signs that the population growth has curbed remarkably in recent years. The number of people aged 65 and older was up 0.5 percent from 2005, numbering 4.56 million, roughly 9.3 percent of the entire population.

Koreans are primarily from one ethnic family and speak one language. Sharing distinct physical characteristics, they are believed to be descendants of several Mongol tribes that migrated onto the Korean Peninsula from Central Asia.
In the seventh century, the various states of the peninsula were unified for the first time under the Silla Kingdom (57 B.C.-A.D. 935). Such homogeneity has enabled Koreans to be relatively free from ethnic problems and to maintain a firm solidarity with one another.
As of the end of 2005, Korea's total population was estimated at 48,294,000 with a density of 474 people per square kilometer. The population of North Korea is estimated to be 22,928,040.
Korea saw its population grow by an annual rate of 3 percent during the 1960s, but growth slowed to 2 percent over the next decade. In 2005, the rate stood at 0.44 percent and is expected to further decline to 0.01 percent by 2020.
A notable trend in Korea's demographics is that it is growing older with each passing year. Statistics show that 6.9 percent of the total population of Korea was 65 years or older in 1999, and 9.1 percent was in 2005.
In the 1960s, Korea's population distribution formed a pyramid shape, with a high birth rate and relatively short life expectancy. However, age-group distribution is now shaped more like a bell because of the low birth rate and extended life expectancy. Youths (15 and younger) will make up a decreasing portion of the total, while senior citizens (65 and older) will account for some 15.7 percent of the total by the year 2020.
The nation's rapid industrialization and urbanization in the 1960s and 1970s was accompanied by continuing migration of rural residents to the cities, particularly Seoul, resulting in heavily populated metropolitan areas. However, in recent years, an increasing number of Seoulites have begun moving to suburban areas.
Religion & Beliefs

Buddhism first arrived in Korea in the 2nd year (A.D. 372) of the reign of King Sosurim of the Goguryeo Kingdom. After its introduction, Buddhism exerted a powerful influence in the Baekje Kingdom and Silla Kingdom. Bulguksa Temple and Seokguram Grotto, which are designated as World Cultural Heritage sites by UNESCO, are Buddhist creations from the Silla Kingdom.
Buddhism has exercised a far-reaching influence on Korean culture throughout its long history. The nation's invaluable Buddhist heritage abides in buildings, sculptures, paintings and handicraft.
Protestantism & Catholicism
Protestantism came to Korea after the signing of the Korean-American Treaty in 1882. Because Christianity challenged the basic values of Joseon society, its believers were subject to persecution in the early years, but as Christians took an increasingly active role in the anti-colonial struggle against the Japanese and churches promoted more educational opportunities, Christianity gained acceptance. Today Korean churches evangelize abroad, and approximately twenty five percent of the Korean population is Christian.
Catholicism first came to Korea as a western scholarly pursuit. Korean tributary missions to the imperial court of China took an interest in Jesuit missionary books and brought them back to Korea. In 1784 the first Korean was baptized in Beijing and returned to Korea to set up a house of worship. Despite considerable persecution by the government, numerous people joined the Catholic Church. Presently, over two million people belong to the church.
Confucianism became a common philosophy in ancient Korea. When it came into contact with fundamental Korean sentiments, Confucianism brought about profound changes and exerted considerable influence on the Korean people. It has been an indispensable component of the Korean moral system, way of life and national laws.
Confucianism, which was the major philosophy of the Joseon Dynasty, eventually gave rise to Silhak, or practical learning. Confucianism has deeply permeated the consciousness of Korean people and can be seen today in many forms, including two ceremonies that continue today: Jongmyo Jerye, the royal ancestral service at Jongmyo Shrine and Seokjeon Daeje, the worship rites at the Seonggyungwan in honor of Confucius, his disciples, and other celebrated Chinese and Korean Confucian scholars.
Various shamanistic practices are deeply ensconced in Korean life. Shamanism was similar with folk beliefs from ancient times. It is closely related to the primitive cults which practiced communal rites for the gods of heaven, and which were uninfluenced by Buddhist tradition. One distinguishing characteristic of Korean shamanism is that it seeks to solve human problems through a meeting between humans and the spirits. This can be seen in the various types of shamanistic rites which are still widely practiced even today.