A few Japanese people, except the local residents, would know how to read the temple name in its Kanji characters, which are used to represent unusual phonetic values. A legend explains the origin of the name like this:
Once there was a county, out of which people one day decided to make a new country, and named the new one "Ototo" (literally meaning "younger brother") comparing the original the older brother ("Ani" in Japanese). Thus, the former was referred to as "Ani Kuni" (Kuni: country or county) while the latter, "Ototo Kuni," which was contracted to become "Oto-Kuni." The Chinese characters presently used used are semantically irrelevant to the original meaning.
The temple belongs to the Buzan School of the Shingon Denomination. Renowned for its magnificient peonies in spring, the temple has the alias of "the Temple of Peonies."
The 26th Emperor Keitai moved the capital city to the County of Otokuni.
A record says the imperial palace for Emperor Keitai was located on the present Otokuni Temple ground.
Year ca. 603
Prince Shotoku constructed the temple following the edict of the 33rd Emperor Suiko.
The construction of the temple presumably coincided with that of Koryuji Temple in Uzumasa (in the southern Kyoto).
According to an archaeological study, the temple was constructed using the ancient Korean measurement system, which was also used for Horyuji Temple in Nara (also built by the same prince). Emperor Suiko was the first female emperor in Japan, and Prince Shotoku, who served as the regent was her nephew.
The principal image of Otokuni temple in those days was the Avalokitesvara (Eleven-faced Bodhisattva).
Year 784 The 50th Emperor Kammu moved the capital city to Nagaoka.
The temple underwent a major extension construction at the occasion of the capital transfer. The enlarged temple premises measured more than 180 meters from the north to the south.
The later Naniwa Palace was located in the ancient city of Naniwa, presently Osaka. The city was built by the 36th Emperor Kotoku, who moved the capital city from Asuka, Nara, shortly after the Great Reforms of Taika Era. The early Naniwa Palace was burned by the fire during the reign of the 40th Emperor Temmu, and his grandson Emperor Shomu (45th) reconstructed the palace (referred as the later palace).
Year 785 Emperor Kammu confined Prince Sawara in the temple.
Sawara was Kammu's younger brother and the Crown Prince. When Fujiwara Tanetsugu, a government official fully trusted by the emperor was assassinated, Sawara was suspected for involvement in the incident and was confined in the temple. He protested his innocence by fasting, but despite his effort, he was sentenced to an exile in Awaji Island. On his way to the island, he died in despair.
After his death, unfortunate incidents happened one after another. Both the emperor's mother and his empress died. The new Crown Prince became ill and epidemics and natural disasters hit the capital. All these misfortunes were attributed to Sawara's resentment, and the emperor endowed him with the posthumous name of " Emperor Sudo" and moved his tomb to Nara from the exiled place.
Year 811 Buddhist Master Kobo became the Head Priest of Otokuni Temple.
Master Kobo (Dharma name: Kukai) is the founder of the Shingon Denomination. Master Saicho (also called Denkyo), Kukai's rival and contemporary priest as well as the founder of the Tendai Denomination, visited him at Otokuni Temple to ask for the initiation into esoteric Shingon teachings, which Saicho didn't have the chance to master.
Both priests visited China in the same delegation to learn Buddhism to the depth. However, Saicho's stay was shorter than that of Kukai, and therefore, the depth of understanding as well as Buddhist scriptures he brought back to Japan fell far behind Kukai's achievement.
Kobo was also a master of calligraphy, and there is the Japanese saying that goes "Even Kobo's drawing brush slips" (meaning nobody is perfect).
The statue, the principal image of worship at the temple, has the images of a deity named Hachiman and Master Kobo incorporated into a single figure. A legend says: When the master was carving his own image, the deity appeared in a figure of old man and proposed a joint sculpture. The old man carved the bust of the master while the master sculptured the head of the deity respectively. Later when these two separately-elaborated parts were put together, they matched perfectly into a single statue without a millimeter gap. The statue is handled as a holy of holies and kept unseen for public eyes.
Also carved by Master Kobo, the Vaishravana (the Big Hearer) statue enshrined here is listed as a National Important Cultural Heritage. Vaishravana is one of the Four Heavenly Kings, Dharma protectors of Buddhism who guard the four cardinal directions of north, south, east and west. Vaishravana is the protector of the north.
Brought from the Western Regions (Xiyu), mandarins were rare delicacy in those days. The master planted the trees in the garden and the fruits were occasionally offered to the Imperial Court.
Year 897 Emperor Uda abdicated the throne. The temple was assigned as the emperor's provisional palace.
The temple was used as a place where the retired emperor would stay during his excursion away from his residence. As the emperor became a Dharma Emperor (ordained into priesthood) after his retirement, the temple began to be called "the Dharma Emperor Temple".
Years 1558 to 1569 The temple was burned in a war.
A war fire caused by Oda Nobunaga, a warrior lord, destroyed the temple.
Year 1693 The 5th Shogun Tokugawa Tsunayoshi reconstructed the temple.
In the Edo Period (1603 to 1867), the temple was reconstructed by Ryuko, the chief abbot of Edo Goji-in (a temple in charge of soliciting prayers in favor of the shogun), who voluntarily assumed the role of administrating Otokuni Temple. He was greatly trusted by the shogun, who entrusted him with the reconstruction of the temple. At this occasion, the temple was officially denominated a Shingon temple and the special law regarding Otokuni Temple was enacted. The temple was assigned as a Tokugawa family's wish fulfilling prayer conductor.
Shogun Tsunayoshi is famous as the Dog Shogun for his enacting the law to prohibit killing animals. Some records say the offenders of the law were severely punished usually by death, but other records say all of such episodes are rootless and the law was never actually applied to commoners.
After going through the hard time caused by the movement to abolish Buddhism in Meiji Period (1868 to 1912), the temple has survived as it is today.
Other notable features of the temple are the belfry with a bamboo-made bell striker (usually made of wood) and oil paper umbrellas placed in the peony fields serving as a shield to protect the flowers from strong sunshine or rain.
For a refreshing break after intensive flowery viewing, a cup of cold Amazake (sweet fermented rice drink) is served for a charge, together with hot tea and a tidbit of bamboo shoots boiled with soy sauce and sugar, at a provisional tea shop. The bamboo shoot is a special product of this region and in the season, it is sold along with other various local food products outside the temple gate as souvenirs.