Thoroughly intent on unifying his realm, Wang chose a central location for the national capital. Kion-chiu, the metropolis of Shinra, was too far south, Ping-an, the royal seat of old Korai, was too far north; but one hundred miles nearer “the river” Han, was Sunto. This city, now called Kai-seng, is twenty-five miles from Seoul and equally near the sea. Wang made Sunto what it has been for over nine centuries, a fortified city of the first rank, the chief commercial centre of the country, and a seat of learning. It remained the capital until 1392 A.D. Wang-ken or Wang, the founder of the new dynasty under which the people were to be governed for over four hundred years, was an ardent Buddhist. Spite of his having put the monk to death to further personal ends, he became the defender of the India faith and made it the official religion. Monasteries were founded and temples built in great numbers. To furnish revenues for the support of these, tracts of land were set apart as permanent endowment. The four centuries of the house of Korai are the palmy days of Corean Buddhism. From China, which at this time was enjoying that era of literary splendor, for which the Sung dynasty was noted, there came an impulse both to scholastic activity and to something approaching popular education. The Nido, or native syllabary, which had been invented by Chul-chong, the statesman of Shinra, now came into general use. While Chinese literature and the sacred books of Buddhism were studied in the original Sanscrit, popular works were composed in Corean and written out in the Nido, or vernacular syllables. The printing press, invented by the Sung scholars, was introduced and books were printed from cut blocks. The Japanese are known to have adopted printing from Corea as early as the twelfth century, when a work of the Buddhist canon was printed from wooden blocks. “A Corean book is known which dates authentically from the period 1317–1324, over a century before the earliest printed book known in Europe.” The use of metal type, made by moulding and casting, is not distinctly mentioned in Corea until the year 1420, and the invention and use of the Unmun, a true native alphabet, seems to belong to the same period. The eleven vowels and fourteen consonants serve both as an alphabet and a syllabary, the latter being the most ancient system, and the former an improvement on it. The unifier of Corea died in 945 and was succeeded by his son Wu. Fifteen years later the last of the five weak dynasties that had rapidly succeeded each other in China, fell. The Chinese emperor proposing, and the Corean king being willing, the latter hastened to send tribute, and formed an alliance of friendship with the imperial Sung, who swayed the destinies of China for the next 166 years (960–1101).