In this image, a large number of jeeps have been parked on a baseball field. The headlights display a V for victory. I searched for other pics or other information about these rallies, but didn’t stumble onto anything.
According to the Library of Congress, this is an Anthracite rally. The Jeep headlights form V for victory at a night rally for Pennsylvania anthracite miners in Wilkes-Barre on September 29th, 1942. Similar rallies were held in other anthracite area cities from September 28th through October 1st 1942.