Complex sentence: Concord takes its name from Concord, Massachusetts, in the USA, which was the site of the Battle of Concord, one of the first military engagements of the American Revolutionary War (1775-1778).
Split into simpler sentences: Concord takes its name from Concord, Massachusetts, in the USA. It was the site of the Battle of Concord, the first military engagements of the American Revolutionary War (1775-1778).