Year 45 BC was either a common year starting on Thursday , Friday or Saturday or a leap year starting on Friday or Saturday ( link will display the full calendar ) ( the sources differ , see leap year error for further information ) and the first year of the Julian calendar and a leap year starting on Friday of the Proleptic Julian calendar .
Year 45 BC was either a common year starting on Thursday , Friday or Saturday or a leap year starting on Friday or Saturday and the first year of the Julian calendar .