Reisai (regular festival) (例祭)

Reisai is a term used to to describe one kind of saishi, religious services that are performed annually at shinto shrines.

Among saishi, reisai is regarded as the most important.

Reisai is held once a year, and in many cases on a day specially associated with the enshrined deity or the shrine. For example, in shrines dedicated to human gods, it is often performed on the birthday or the death day of the sacred person. If there is no such commemorative day, a spring festival or an autumn festival is regarded as reisai. Reisai is held on a given date every year and no one is allowed to change the date in vain. Even after World War II, shrines administered by Jinja-Honcho (The Association of Shinto Shrines) need to require approval from the Jinja-Honcho to change the date of reisai.

History
It is only in recent times that the name 'reisai' has come into use. Before then, it was known as 'oomatsuri', 'onmatsuri' or the host shrine's name with the suffix meaning a festival, such as 'Kasuga-Matsuri' Festival or 'Iwashimizu-Sai' Festival, was used. In recent times, the phrase 'The xxxx shrine reisai, xxth day of xxxx' can be found on posters for noted places in various regions. This indicates that the custom of using 'reisei' to describe a shrine's most important festival is firmly established.

Under the shinto shrine system of the Meiji period, reisai, together with festivals such as the Kinensai festival (to pray for a good crop) and the Niiname-sai festival (ceremonial offering by the Emperor of newly-harvested rice to the deities), were designated 'taisai' (grand festivals). As a result, the reisai at national and Imperial shrines, prefectural shrines, village shrines and certain town shrines (those appointed to accept offerings of food, alcohol and gifts of monery wrapped in paper called heihakuryo), were attended by imperial envoys or heihaku kyoshinshi (special imperial messengers) who carried came to offer heihaku (paper or silk cuttings or red and white cloth presented to deities) presented by the state or the Imperial house.

The system of heihaku presentation by the state was abolished after World War II. However, imperial envoys (chokushi) still attend reisai at shrines designated as Chokusai-sha (shrine attended by imperial envoy).
For other shrines, the official heihaku presentation system was replaced with "honcho-hei' offerings from Jinja-Honcho. (However, this is true only of shrines administered by Jinja-Honcho.)

Name
Under the classification of religious services, reisai are classified as 'taisai'. For that reason, reisai are sometimes called rei-taisai (regular grand festival). However, this is a colloquial name, not the formal one (although some reisai are popularly referred to as 'xxxx Shrine Rei-taisai Festival').

The formal name is Taisaishikireisai (regular festival in the form of grand festival).

Religious services other than the formal 'reisai' sometimes include the word 'reisai' in their name (e.g. 'Spring Reisai Festival'), but there is only one reisai in one shrine.

Date of head shrine's reisai

There is no concept of 'reisai' at Ise-jingu Shrine. However, Kannamesai (held on Oct.17), which is the shrine's most important religious service, is equivalent to the reisai performed at ordinary shrines.