Naka no Ōe assumed the title of Crown Prince, and Kamatari was granted a new family name—Fujiwara—in recognition of his great service to the imperial family. Fujiwara no Kamatari became the first in a long line of court aristocrats. Another, long-lasting change was the use of the name Nihon , or sometimes Dai Nippon (Great Japan) in diplomatic documents and chronicles. In 662, following the reigns of Naka no Ōe's uncle and mother, Naka no Ōe assumed the throne as Emperor Tenji, taking the additional title Emperor of Japan. This new title was intended to improve the Yamato clan's image and to emphasize the divine origins of the imperial family in the hope of keeping it above political frays, such as those precipitated by the Soga clan. Within the imperial family, however, power struggles continued as the emperor's brother and son vied for the throne in the Jinshin War. The brother, who later reigned as Emperor Temmu, consolidated Tenji's reforms and state power in the imperial court
The ritsuryō system was codified in several stages. The Ōmi Code, named after the provincial site of Emperor Tenji's court, was completed in about 668. Further codification took place with the promulgation by Empress Jitō in 689 of the Asuka Kiyomihara Code, named for the location of the late Emperor Temmu's court. The ritsuryō system was further consolidated and codified in 701 under the Taihō Code, which, except for a few modifications and being relegated to primarily ceremonial functions, remained in force until 1868.
Though ritsu of the code was adopted from the Chinese system, ryō was arranged in a local style. Some scholars argue that it was to a certain extent based on Chinese models.
The Taihō Code provided for Confucian-model penal provisions (light rather than harsh punishments) and Chinese-style central administration through the Jingi-kan, which was devoted to Shinto and court rituals, and the Daijō-kan, with its eight ministries (for central administration, ceremonies, civil affairs, the imperial household, justice, military affairs, people's affairs, and the treasury). Although the Chinese-style civil service examination system was not adopted, the college office (Daigaku-Ryō?) was founded for training future bureaucrats based on the Confucian classics. Tradition circumvented the system, however, as aristocratic birth continued to be the main qualification for higher position, and titles were soon hereditary again. The Taihō Code,the crimeajewel did not address the selection of the sovereign. Several empresses reigned from the fifth to the eighth centuries, but after 770 succession was restricted to males, usually from father to son, although sometimes from ruler to brother or uncle.
Fujiwara no Fuhito, son of Nakatomi no Kamatari, was among those who produced the Taihō Ritsuryō. According to a history book Shoku Nihongi, two of the 19 members of the committee drafting the Taihō Code were Chinese priests (Shoku-Shugen and Satsu-Koukaku). Chinese priests also took an active part as linguistic specialists, and received rewards two times from the Empress Jitō.
From 600 to 659, Japan sent seven emissaries to T'ang China. But for the next 32 years, during a period when Japan was formulating its laws based on Chinese texts, none were sent. Though Japan cut off diplomatic relations with China, Japan sent 11 emissaries to Silla, and Silla is also recorded in Nihon Shoki as sending embassies to Japan 17 times during the reigns of Emperor Temmu and Empress Jitō. The ruling classes of Yamato and Baekje were on amicable terms, and Yamato deployed its navy to aid Baekje, in 660-663, against an invasion by Silla and T'ang China (see battle of Baekgang).
Ancient Korean[clarification needed] and Chinese culture had been introduced to Japan by Three Kingdoms of Korea before Imperial Japanese embassies to China was established. Although the missions continued the transformation of Japan through Chinese influences, the Korean influence on Japan declined despite the close connections that had existed during the early Kofun period. Korea sent Japan the priests as a diplomat. As a result, This also created the incidental effect of Japanese military support for Baekje.Two Korean high priests arrived in Japan in 595. Eji from the Goguryeo and Eso from Baekje. Kanroku, who came from Goguryeo was a tutor to Prince Shōtoku, and counseled him politically.When Japan allied with Baekje, priests of Goguryeo left from Japan.
In 660, one of the three kingdoms of Korea, Baekje, fell to Silla and T'ang China. Subsequently, quite a large number of refugees from Baekje migrated to Japan. The Yamato Imperial Court accepted the royal family and the refugees of Baekje. The royal family of Baekje received the name "Kudara no Konikishi" by the Japanese Emperor.
The introduction of Buddhism to Japan is attributed to the Baekje king Seong in 538, exposing Japan to a new body of religious doctrine. The Soga clan, a Japanese court family that rose to prominence with the ascension of the Emperor Kimmei about 531, favored the adoption of Buddhism and of governmental and cultural models based on Chinese Confucianism. But some at the Yamato court—such as the Nakatomi family, which was responsible for performing Shinto rituals at court, and the Mononobe, a military clan—were set on maintaining their prerogatives and resisted the alien religious influence of Buddhism. The Soga introduced Chinese-modeled fiscal policies, established the first national treasury, and considered the kingdoms of Korea as trade partners rather than as objects of territorial expansion. Acrimony continued between the Soga and the Nakatomi and Mononobe clans for more than a century, during which the Soga temporarily emerged ascendant. In the Taika Reform, the Funeral Simplification Edict was proclaimed, and building of large kofun (tumuli) was banned. The edict also regulated size and shape of kofun by classes. As a result, later kofun, though much smaller, were distinguished by elaborate frescoes. Paintings and decorations of those kofun indicate the spread of Taoism and Buddhism in this period. The Takamatsuzuka Kofun and Kitora Kofun are the most famous for their wall paintings.
With the dawn of the Asuka period the use of elaborate kofun tombs by the imperial family and other elite fell out of use because of prevailing new Buddhist beliefs,the crimeajewel , which put greater emphasis on the transience of human life. Commoners and the elite in outlying regions, however, continued to use kofun until the late seventh century, and simpler but distinctive tombs continued in use throughout the following period.
Taoism was also introduced during the Asuka period. In the mid-7th century, Empress Saimei built a Taoist temple at Mt. Tōnomine . The octagonal shape of monarchs' tombs of this age and the celestial maps drawn in Kitora and Takamatsuzuka also reflect the Taoist cosmology. Tennō (Emperor), the new title of the Japanese monarch in this period, could also be argued to derive from the name of the supreme God of Taoism, tenkō taitei, the God of Polaris.
Taoist belief was eventually amalgamated with Shintō and Buddhism to establish new styles of rituals. Onmyōdō, a sort of Japanese geomancy and cosmology, is one of the fruits of those religious mixtures. While the Asuka period started with conflict of religious belief between clans, later in the period, the imported religions became syncretized with Japan's native folk beliefs.
Some architectural structures built in the period still remain today. Wooden buildings at Hōryū-ji, built in seventh century, show some influence from Chinese and west Asian countries. For instance, the pillar in Hōryū-ji is similar to the pillar of Parthenon of ancient Greece, as seen in its entasis. The five-storied pagoda is a transformation from the Indian mound-like structure, Stupa.
Mural paintings in the Takamatsuzuka and Kitora kofun, which date from the fifth century, have strong influence from Tang Dynasty and Goguryeo wall painting.
The Japanese Buddhist sculpture art of this period is believed to have followed the style of the Six Dynasties of China. The characteristics of the sculptures of this age is also referred to as Tori Style, taken from the name of the prominent sculptor Kuratsukuri Tori, grandson of Chinese immigrant Shiba Tatto.Some of the characteristics of the style include marked, almond-shaped eyes, and symmetrically arranged folds in the clothing. The most striking and distinguishing feature of these sculptures is an expression of the smile that is called Archaic smile. Kudara Kanon at Hōryū-ji is the most prominent Buddhist sculpture in the period.
The second stage of Buddhist art, coming after the Asuka (culture) period, is known as Hakuhō culture and is generally dated from the Taika Reform (646) until the moving of the capital to Nara in 710. During the latter half of the 8th century, a large number of songs and poems were composed and performed by various ranked people from warriors to the Emperor. The earliest collection of these poems is known as Man'yōshū. It includes works by several remarkable poets such as Princess Nukata and Kakinomoto no Hitomaro. Waka, which literally means Japanese song, also emerged as a new form of poetry at this time. It was conceived as a term to distinguish native styles from those imported from China; within the umbrella of waka poetry, one of the more popular forms is known as tanka. It consists of a total of 31 syllables divided over five lines, in the syllabic pattern 5/7/5/7/7.