1819 followed by 1820
1819 (MDCCCXIX) was a common year starting on Friday of the Gregorian calendar and a common year starting on Wednesday of the Julian calendar, the 1819th year of the Common Era (CE) and Anno Domini (AD) designations, the 819th  year of the 2nd millennium, the 19th  year of the 19th century, and the  10th  and last year of the 1810s decade. As of the start of 1819, the Gregorian calendar was 12 days ahead of the Julian calendar, which remained in localized use until 1923.