The first time:

1, the name changed from big to new (learning the feudal system of Sui and Tang Dynasties)

2. The reigning emperor: Emperor Kotoku

3. Time: 646 (the first year of Dahua)

4. Historical significance: making Japan transition from a slave society to a feudal society.

The second time:

1, the name of Meiji Restoration (learning from western advanced capitalism)

2. The reigning emperor: Emperor Meiji

3. Time: 65438+the middle of the 9th century.

4. Historical significance: it has promoted the progress of Japanese society, freed Japan from the national crisis, and since then embarked on the road of developing capitalism and became the largest country in Asia (positively). However, it retained a large number of feudal remnants and embarked on the road of foreign colonial expansion, which became a new threat (negative aspect) to peace in Asia.