Short answers, pulled from the story.
Georges Ernest Boulanger was a French Army officer and politician who lived from the 29th of April 1837 to the 30th of September 1891. He became enormously popular during the Third Republic and was known by the nickname General Revenge, Général Revanche, for his calls for revenge against Germany.
Georges Ernest Boulanger earned the nickname Général Revanche, General Revenge, because of his appeals to French desire for revenge against Imperial Germany while serving as Minister of War. Supporters came to see him as the man destined to deliver that revenge.
Georges Ernest Boulanger's movement, known as Boulangisme, suffered a decisive defeat in the elections of September 1889. New electoral laws barred him from running in multiple constituencies at once, and combined with government opposition and his own self-imposed exile, the movement collapsed rapidly.
Georges Ernest Boulanger fled Paris on the 1st of April 1889 after the government issued a warrant for his arrest on charges of conspiracy and treasonable activity. He went first to Brussels and then to London, and on the 4th of April Parliament stripped him of his immunity from prosecution.
Georges Ernest Boulanger died by suicide on the 30th of September 1891, shooting himself in the head at the Ixelles Cemetery in Brussels. He died on the grave of his mistress, Madame de Bonnemains, who had died in his arms the previous July, and he was buried in the same grave.
Georges Ernest Boulanger's movement, Boulangisme, is interpreted differently by historians. Scholars such as Zeev Sternhell describe it as an early right-wing form of fascism, while historians such as Jacques Néré and Irvine argue it was fundamentally a popular movement of the extreme left.