From Korean Tripitaka: "The entire Korean Tripitaka was carved twice during the Koryo Dynastry (918-1392), both times on wooden blocks. The king and the people believed that the presence of these sacred texts would help to drive back invasions and also bring good luck."
From Wikipedia: "The Tripitaka Koreana was first carved in 1087 when Goryeo was invaded by the Khitan in the Third Goryeo-Khitan War. The act of carving the woodblocks was considered to be a way of bringing about a change in fortune by invoking the Buddha's help. The original set of woodblocks were destroyed during the Mongol invasions of Korea in 1232, when Goryeo's capital was moved to Ganghwa Island during nearly three decades of Mongol attacks, although scattered parts of its prints still remain. King Gojong thereafter ordered the revision and re-creation of the Tripitaka; the carving took 16 years, from 1236 to 1251. This second revision is usually what is meant by the Tripitaka Koreana. In 1398, it was moved to Haeinsa, where they have remained housed in four buildings."
Life in Korea adds: "The original set took 77 years to complete, and was finished in 1087. However, it was destroyed in 1232 by a Mongol invasion. King Kojong ordered the set remade and work began in 1236. It was felt that replacing the wood blocks would convince Buddha to intervene and help repel the Mongolian invaders. Originally carved on Kangwha Island, they were moved to Haein-sa during the early years of the Yi dynasty."
Korean Tripitaka concludes: "The Korean Tripitaka has great national significance to the Korean people. It represents their steadfastness in adversity and their wish to maintain their cultural identity. In some ways it is the national conscience of Korea."
This collection of iconic texts imbued with both religious and nationalistic significance is doubly fascinating because it is the print blocks, not the printed texts produced from them, that were given and have retained such revered status. Perhaps that is because the wooden blocks are materially larger and more substantial and take much longer to create than printed paper books and so are better suited to veneration as monuments.