upright=1.35|thumb|King Clovis IV and Pepin of Herstal __NOTOC__ Year 691 (DCXCI) was a common year starting on Sunday of the Julian calendar. The denomination 691 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.
upright=1.35|thumb|King Clovis IV and Pepin of Herstal __NOTOC__ Year 691 (DCXCI) was a common year starting on Sunday of the Julian calendar. The denomination 691 for this year has been used since the early medieval period when the Anno Domini calendar era became the prevalent method in Europe for naming years.