1904 (MCMIV) was a leap year starting on Friday of the Gregorian calendar and a leap year starting on Thursday of the Julian calendar, the 1904th year of the Common Era (CE) and Anno Domini (AD) designations, the 904th year of the 2nd millennium, the 4th year of the 20th century, and the 5th year of the 1900s decade. As of the start of 1904, the Gregorian calendar was 13 days ahead of the Julian calendar, which remained in localized use until 1923.
