Sentence:  As for the <WSD>Nones</WSD>, it was thought that the multitudes should avoid mass meetings then because after the kings were expelled, the Roman people particularly celebrated what they took to be Servius Tullius's birthday: because crowds notoriously thronged all the <WSD>Nones</WSD>—it being well-known that Servius was born on the <WSD>Nones</WSD>, though the exact month was uncertain—those in charge of the calendar were afraid that if the whole population gathered on a market day it might start to revolt out of yearning for the king, and so they took the precaution of keeping the <WSD>Nones</WSD> and market days distinct. 
Meaning of the word marked with <WSD> tags:  The notional first-quarter day of a Roman month, occurring on the 7th day of the four original 31-day months (March, May, Quintilis or July, and October) and on the 5th day of all other months.