To correctly match the first date on the timeline, we would need to know what that date is. However, given that the events listed are all significant occurrences during the American Revolutionary War, we can align them with their known dates:
- The Battle of Lexington and Concord occurred on April 19, 1775.
- The Declaration of Independence was adopted on July 4, 1776.
- The Battle of Saratoga took place in September and October of 1777.
- Cornwallis surrendered at Yorktown on October 19, 1781.
If the first date on the timeline is April 19, 1775, then the corresponding event would be "The Battle of Lexington and Concord." If you can provide the specific first date, I can give a more definitive answer.