The events shown beginning at the 06:16 mark are of a "Crossing the Line" ceremony. When a naval ship crosses the equator, those not initiated into King Neptune's order (Polliwogs) are subpoenaed before the court of Neptune, and are then "tried" by King Neptune's loyal order, or "Shellbacks". Once complete, the 'Wogs' become 'Shellbacks' and are allowed to participate in the initiation rights when the ship again crosses the line. Ceremonies in earlier years were known to be quite rough, with verbal and physical abuse common. Today's ceremonies are highly regulated for safety reasons.
The battleship shown at the 9:08 mark firing broadside is the USS North Carolina, BB-55 during the invasion of Iwo Jima.
Most of Robert Sherrod's dialogue is taken from his book "Tarawa: The Story of a Battle "