1635 (MDCXXXV) was a common year starting on Monday of the Gregorian calendar and a common year starting on Thursday of the Julian calendar, the 1635th year of the Common Era (CE) and Anno Domini (AD) designations, the 635th year of the 2nd millennium, the 35th year of the 17th century, and the 6th year of the 1630s decade. As of the start of 1635, the Gregorian calendar was 10 days ahead of the Julian calendar, which remained in localized use until 1923.
