1816 followed by 1817
1816 (MDCCCXVI) was a leap year starting on Monday of the Gregorian calendar and a leap year starting on Saturday of the Julian calendar, the 1816th year of the Common Era (CE) and Anno Domini (AD) designations, the 816th  year of the 2nd millennium, the 16th  year of the 19th century, and the  7th   year of the 1810s decade. As of the start of 1816, the Gregorian calendar was 12 days ahead of the Julian calendar, which remained in localized use until 1923.  
This year was known as the Year Without a Summer, because of low temperatures in the Northern Hemisphere, possibly the result of the Mount Tambora volcanic eruption in Indonesia in 1815, causing severe global cooling, catastrophic in some locations.