Oath of the Horatii - Jacques-Louis David

Jacques-Louis David (French, August 1748 – December 1825) was an influential French painter in the Neoclassical style, considered to be the preeminent painter of the era. In the 1780s his cerebral brand of history painting marked a change in taste away from Rococo frivolity toward a classical austerity and severity, heightened feeling chiming with the moral climate of the final years of the Ancien Régime.

The "Oath of the Horatii" is one of his famous works.

source: http://en.wikipedia.org/wiki/Jacques-Louis_David
website: http://www.jacqueslouisdavid.org/