I have read somewhere on the internet that the guests would wear dark or simple color not to catch much attention or you can wear kimono like houmongi, yeh seems like wedding rules, because at the wedding the bride have to be the most beautiful, black seems a unlucky color but in Japan that's their tradition.

@@milkymilky2543 thank you so much. In my country, we don't wear black on someone's wedding even men don't wear black suit also.

Shrine shrine maiden( ´ω` )/

Japanese weddings themselves and the traditions in which they were held were greatly influenced by Shintoism, Japan's original religion, but weddings themselves were usually held at home. It was not until the wedding of Crown Prince Yoshihito (later Emperor Taisho) and Princess Setsuko Kujo (later Empress Teimei) on May 10, 1900, that the "Shinto wedding ceremony" format became clear and widespread. It was the first time that a wedding ceremony was held in front of the Imperial Palace's Kenjo-daizen, and the public's desire for a similar Shinto wedding ceremony grew. In response to the growing momentum, the Jingu Bongan-kai (present-day Tokyo Grand Shrine) in Tokyo established a civilian "Shinto wedding" style based on the imperial wedding ceremony, and held a mock wedding ceremony on March 3, 1901. The style of the "Shinto wedding ceremony" practiced today is based on the one established by the Jingu Bonenkai. Japanese translation of

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