 Both memorials incorrectly date the battle to April 18, likely an error of Hubbard's that was subsequently reprinted.The date is April 21 in Mather's contemporary chronicle, and a letter dated April 21, 1676 from the colonial government of Massachusetts Bay to Plymouth Colony governor Josiah Winslow states, "This day we have intelligence in the general that Sudbury was this morning assaulted and many houses burnt down.