The "Peacemaker's Day" speech was a famous speech issued by General Bouris Ulgo during the Cold War that saw him declare himself King of the planet Alderaan. He issued the speech before a group of his soldiers, but broadcast the speech across the planet. Ulgo's declaration sparked full-fledged civil war.
Sources[]
Signs of War Trailer on The Old Republic's official website (backup link) (First pictured)- Star Wars: The Old Republic Encyclopedia (First identified as Peacemaker's Day)