1709

1709 (MDCCIX) was a common year starting on Tuesday of the Gregorian calendar and a common year starting on Saturday of the Julian calendar, the 1709th year of the Common Era (CE) and Anno Domini (AD) designations, the 709th year of the 2nd millennium, the 9th year of the 18th century, and the 10th and last year of the 1700s decade. As of the start of 1709, the Gregorian calendar was 11 days ahead of the Julian calendar, which remained in localized use until 1923.

In the Swedish calendar it was a common year starting on Friday, one day ahead of the Julian and ten days behind the Gregorian calendar.