Proper Attire for the Victorian Groom
The dress of the bridegroom is regulated by that chosen by the bride; if she wears a white veil, he is expected to appear in black trousers, dress coat, which may be either black or blue, white waistcoat, and white cravat; or, if a naval or military person, in full uniform. If the bride should prefer to wear a bonnet, the bridegroom should put on a frock-coat of black, brown, or other tasteful color, and light-colored waistcoat and trousers."
[From: "The Bazar Book of Decorum. The care of the Person, Manners, Etiquette, and Ceremonials." 1873]