1584

1584 (MDLXXXIV) was a leap year starting on Sunday of the Gregorian calendar and a leap year starting on Wednesday of the Julian calendar, the 1584th year of the Common Era (CE) and Anno Domini (AD) designations, the 584th year of the 2nd millennium, the 84th year of the 16th century, and the 5th year of the 1580s decade. As of the start of 1584, the Gregorian calendar was 10 days ahead of the Julian calendar, which remained in localized use until 1923.