1066 (MLXVI) was a common year starting on Sunday of the Julian calendar, the 1066th year of the Common Era (CE) and Anno Domini (AD) designations, the 66th year of the 2nd millennium and the 11th century, and the 7th year of the 1060s decade. As of the start of 1066, the Gregorian calendar was 6 days ahead of the Julian calendar, which was the dominant calendar of the time.