Original sentence: However, the destruction of their villages and stored food at the start of winter weakened the Cheyenne more than did the initial military attack.The attack on the Cheyenne in the early winter months was a result of the fact that then the Indians tended to be less mobile and more concentrated at that time.The battle was precipitated by Indian attacks on settlers during the summer and autumn of 1868
Edited sentence: The battle was caused by Indian massacres of settlers during the summer and autumn 1868