Complex sentence: In retaliation for frontier raids by hostile Lenape and British, Colonel Daniel Brodhead of the American militia ignored the treaty and destroyed the Lenape at Coshocton in April 1781.
Split into simpler sentences: In retaliation for frontier raids by hostile Lenape and British, Colonel Daniel Brodhead of the American militia ignored the treaty. He attacked and destroyed the Lenape at Coshocton in April 1781.