Before Julius Caesar's reforms, this was the tenth month in the Roman calendar
The ninth month became September, the tenth month became 
October, the... [DOC] [TLE] the pre-Julian Roman calendar - Tyndale House [PAR] The Roman civil year was normally divided into 12 months: Ianuarius, Februarius
, ... most notably before and after the reforms introduced by Julius Caesar in .... 
month) through December (10th month) are clear evidence that the calendar year
... [DOC] [TLE] A brief history of the calendar - Ancient Roman History Timeline [PAR] Provides a chronological history of Ancient Rome with extensive links to internet 
... plainly appears by the name of the last, December, meaning the tenth month; 
and ...