Passage: The History of the Decline and Fall of the Roman Empire is a six-volume work by the English historian Edward Gibbon. It traces Western civilization (as well as the Islamic and Mongolian conquests) from the height of the Roman Empire to the fall of Byzantium. Volume I was published in 1776 and went through six printings. Volumes II and III were published in 1781; volumes IV, V, and VI in 1788–1789.The six volumes cover the history, from 98 to 1590, of the Roman Empire, the history of early Christianity and then of the Roman State Church, and the history of Europe, and discusses the decline of the Roman Empire among other things.

Question: When was the first volume of the history of the decline and fall of Roman empire published?
1776