(Definition of harp on (about sth) from the Cambridge Advanced Learners Dictionary & Thesaurus Â© Cambridge University Press).
Battle of Saratoga. In late September and during the first week of October 1777, Gate's American army was positioned between Burgoyne's army and Albany. On October 7, Burgoyne took the offensive. The troops crashed together south of the town of Saratoga, and Burgoyne's army was broken. In mop-up operations 86 percent of Burgoyne's command was captured.
On 17 June 1775, the same day that George Washington was commissioned general and commander-in-chief of the Continental Army, British and American forces engaged in the first major pitched battle of the Revolutionary War at Bunker Hill, Massachusetts.