Antonyms of anecdote:
annals, biography, chronicle, history, memoir.
Examples of usage:
  1. But the poem deserves a further illustration, and we shall take an opportunity of pointing out some of its most striking beauties; but before we speak of these, we beg leave to relate the following anecdote.
    "The Lives of the Poets of Great Britain and Ireland (1753),Vol. V.", Theophilus Cibber.
  2. This anecdote also is cited as a proof of his indifference as to diet.
    "Plutarch's Lives Volume III.", Plutarch.
  3. Says an English writer: " From the anecdote related respecting the weight of smoke, the vapor of the pipe certainly did not throw a cloud over the brilliant wit of the unfortunate Raleigh."
    "Tobacco; Its History, Varieties, Culture, Manufacture and Commerce", E. R. Billings.