The line-crossing ceremony is a worldwide naval tradition that commemorates a sailor's first equatorial crossing. No one is sure how it started; however, according to accounts, the ceremony has been around at least 400 years. All crew members who have not crossed the equator must endure this sometimes gruelling initiation ceremony. Upon completion of the ceremony, which is purportedly designed to test a sailor's seaworthiness, sailors are welcomed into the seafaring brotherhood. While there are many variations, there are certain ceremonial rituals that must be observed.
Prepare the ship for the arrival of King Neptune and his royal court. The royal court, comprised of the highest-ranking shellbacks (experienced sailors who have already crossed the equator), includes King Neptune and his queen, Davy Jones, the royal baby and other dignitaries.
Entertain the royal court. The evening prior to the equatorial crossing, pollywogs (those who are about to cross for the first time) are summoned to the fantail to dance, recite poetry, sing or tell stories.
Receive a summons to appear before the royal court. Pollywogs must answer various charges levied against them by shellbacks.
Appear on the flight deck or its equivalent the following day. After breakfast, pollywogs strip down to their underwear or wear their clothes inside out and backward, and crawl across the deck to where King Neptune and his court sit in judgment.
Participate in a variety of activities. First-hand accounts recall being forced to dress as women and participate in fashion shows, or to crawl through a garbage-filled canvas tube.
Kneel before the judge and kiss the royal baby's belly. Oftentimes, the royal baby's belly was covered in grease and the shellback pretending to be the royal baby would rub the polliwog's face all over his belly. According to other first-hand accounts, the royal baby would keep a bucket full of mustard behind him. When a pollywog "kissed" him, the shellback would hit the pollywog with a handful of mustard.
Take a royal bath. According to one first-hand account, the bath was a pool about four feet deep and seven feet square that was filled with seawater and diesel oil.
Transition from pollywog to shellback. New shellbacks receive a certificate of acknowledgement.
Sailors that cross the 180th meridian, or International Date Line, are called golden shellbacks.