Original: Year 1813 (MDCCCXIII) was a common year starting on Friday (link will display the full calendar) of the Gregorian calendar and a common year starting on Wednesday of the 12-day slower Julian calendar.
Simplified: Year 1813 (MDCCCXIII) was a year starting on Friday of the Gregorian calendar (or a year starting on Wednesday of the 12-day slower Julian calendar).