12 BC became the prevalent method in Europe for naming years. <onlyinclude> </onlyinclude> 12 BC Year 12 BC was either a common year starting on Saturday, Sunday or Monday or a leap year starting on Sunday (link will display the full calendar) of the Julian calendar (the sources differ, see leap year error for further information) and a common year starting on Friday of the Proleptic Julian calendar. At the time, it was known as the Year of the Consulship of Messalla and Quirinius (or, less frequently, year 742 "Ab urbe condita"). The denomination 12 BC for this year has been used
Military campaigns of Julius Caesar succession. Caesar tightly regulated the purchase of state-subsidised grain and reduced the number of recipients to a fixed number, all of whom were entered into a special register. From 47 to 44 he made plans for the distribution of land to about 15,000 of his veterans. In 63 BC Caesar had been elected Pontifex Maximus, and one of his roles as such was settling the calendar. A complete overhaul of the old Roman calendar proved to be one of his most long lasting and influential reforms. In 46 BC, Caesar established a 365-day year with a leap year every fourth