AUGUST (originally Sextilis), the sixth month in the pre-Julian Roman year, which received its present name from the emperor Augustus. The preceding month Quintilis, had been called "July" after Julius Caesar, and the emperor chose August to be rechristened in his own honour because his greatest good fortune had then happened. In that month he had been admitted to the consulate, had thrice celebrated a triumph, had received the allegiance of the soldiers stationed on the Janiculum, had concluded the civil wars, and had subdued Egypt. As July contained thirty-one days, and August only thirty, it was thought necessary to add another day to the latter month in order that the month of Augustus might not be in any respect inferior to that of Julius.
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)