Second lines are said to have originated from the styles of traditional West African dance circles. Enslaved Africans brought to the United States incorporated these rituals into brass band processionals come to be known as jazz funerals. These parades began as neighborhood celebrations organized by community members to offer social aid to the formerly enslaved and advertise services like loans, funeral services, insurance, and education programs. These gatherings were also used as a way to honor those who had rejoined the ancestors and while African Americans were primarily the participants, many second lines welcome members of the Native Mardi Gras Nation and the two cultures share instruments, costumes and customs.
There are typically two parts of a Second Line -- the first, or main line, being made up of the grand marshal or parade leader, the band, and whoever is being honored. For example, for funerals this includes family and pallbearers who carry the hearse and for weddings the bride and groom. Everyone who falls in line behind make up the "second line" -- those gathered In the revels which invariably includes a brass band and a drumline.
Though paraders are encoruaged to wear ornate costumes and masks and carry whatever props suit them, there are a few staples in a second line -- the umbrella and the handkerchief. For wedding second lines the groom often carries an oversized black umbrella and the bride a white one. Those who could not afford or simply did not have umbrellas and parasols, would simply wave a white handkerchief instead.