Edward Gibbon's Collection
Edward Gibbon (1737 - 1794) was an English historian and member of Parliament, most known for his History of the Decline and Fall of the Roman Empire. The author spent a good part of his life working on Decline and Fall, and as each volume was undertaken he compared it to the birth of a child. His theory is not without criticism, but in general the causes of the Fall were the weakening of civic "Roman" virtues (such as their military spirit), the apathy that Christianity bred in its culture, and the eventual invasion of barbarian hordes that had become a fixture of Rome and its territories. Whatever the legacy of his work, Gibbon's use of primary sources over secondary texts cemented his fame as the "first modern historian."
Edward Gibbon's massive and masterful six volume work is a hefty undertaking. But it's cited as the model on which modern historians base their inquiries into the past. The books cover Roman history from 180 AD to 1590, a period from Marcus Aurelius to a time not too distant from Gibbon's own. .