Sentence:  If at the birth of the Latin kings their fathers were really unknown, the fact points either to a general looseness of life in the royal family or to a special relaxation of moral rules on certain occasions, when men and women reverted for a season to the licence of an earlier age. Such <WSD>Saturnalias</WSD> are not uncommon at some stages of social evolution. 
Meaning of the word marked with <WSD> tags:  A period or occasion of general license, in which the passions or vices have riotous indulgence; a period of unrestrained revelry.