1615 followed by 1616
1615 (MDCXV) was a common year starting on Thursday of the Gregorian calendar and a common year starting on Sunday of the Julian calendar, the 1615th year of the Common Era (CE) and Anno Domini (AD) designations, the 615th  year of the 2nd millennium, the 15th  year of the 17th century, and the  6th   year of the 1610s decade. As of the start of 1615, the Gregorian calendar was 10 days ahead of the Julian calendar, which remained in localized use until 1923.