The US garrison flag of Fort Mercer, 1777, during the Battle of Red Bank and Battle of Fort Mifflin. The flag features a red canton, thirteen white stars, and thirteen alternating blue and white stripes. Proportions are approximate as sources differ.
Own work based on: https://www.gloucestercountynj.gov/686/Forts-of-the-American-Revolution---Fort-
Shorepine