Focus on Le Rêve (Detaille) and analyze the Description.
Le Rêve is a painting depicting the military - the specialty of its creator, Édouard Detaille. It shows an encampment of sleeping French soldiers that continues as far as the eye can see. The soldiers are young conscripts of the French Third Republic who are taking part in summer exercises, probably in Champagne. They are dreaming of the glory of their predecessors, and of exacting revenge following their country's defeat in the Franco-Prussian War.In a patriotic allegory, French soldiers from previous battles are depicted in the sky above in an intentionally indistinct way. They include soldiers from the French Revolutionary Army, as well as those involved in the battles of Austerlitz, Trocadero, Magenta and Solferino, the invasion of Algiers and the defeats at Gravelotte and Reichshoffen in 1870. 
This type of painting corresponds well with the sentiment of the time, evoking nostalgia for a unified, victorious France, and acting as a memento of a mythical France that was edging further into the past. For Detaille, creating this painting was to "take a direct political position", showing his support for nationalist general Georges Boulanger, as well as celebrating the army.
Édouard Detaille Austerlitz Franco-Prussian War Solferino Georges Boulanger Reichshoffen Gravelotte French Third Republic French Revolutionary Army Magenta Champagne Trocadero the invasion of Algiers