Jacques David, Oath of Horatii. 1784
It came about when the French Revolution was taking off, and it became a symbol of the french revolution.
Theme: Loyalty, bravery, duty to country. The three sons of Horatius swear to defend Rome with their lives. There is also the idea of gender differences at the time. Men take war more idealistically, where the lines of the three brothers point directly at the swords, while the women in the background give the impression of the cost of the war with their faces turned away from the swords. They are concerned about the loss of their loved ones.
Technique: It compresses space and forces you to concentrate on the figures on the foreground. This treatment of space made way for the flattening of space in modernist painting.