Kim Jong Un took to the podium to mark the 100th birthday of national founder Kim Il Sung.
Thousands gathered on the days leading up to the festivities to rehearse for the big event that came after a failed rocket launch.
The U.S. claims the launch was a covert test of long-range missile technology. However, Pyongyang space officials maintain the rocket was meant to send a satellite into orbit to study crops and weather patterns.
During his speech, Kim Jong Un said the era when nuclear arms could be used to threaten his country was "forever over."
The speech and following military parade culminated with the unveiling of a new long-range missile. It's not clear how powerful or significant the addition to the North Korean arsenal is.
Kim's speech took North Koreans by surprise. His father, the late leader Kim Jong Il, addressed the public only once in his lifetime.
The Associated Press contributed to this report.