The Frisian flag (Friese vlag or vlag van Friesland), is the official flag of the Dutch province of Friesland.
It consists of four blue and three white diagonal stripes; in the white stipes are a total of seven red pompeblêden, stylised heart-shaped leaves of yellow water-lily. The jerseys of the football club sc Heerenveen and the Blauhúster Dakkapel are modeled after this flag.
The seven red pompeblêden are a reference to the Frisian "sea countries" in the Middle Ages: independent regions along the coast from Alkmaar to the Weser who were allianced against the Vikings. There were never precisely seven distinct rulers, but the number seven probably has the connotation "many." Some sources hold, however, that there have been seven Frisian lands: West Friesland, Westergoa, Eastergoa, Hunsingo, Fivelingo, Emsingo, and Jeverland.
The pompeblêden are used in other related flags such as the flag of the Ommelanden in neighbouring Groningen Province, a historically Frisian area, and for a proposed pan-Frisia flag put forth by the Groep fan Auwerk.
Since the 11th century a coat of arms with pompeblêdden is known. Evidence herefore lies within verses of the Gudrunlied. Round 1200 Scandinavian coats of arms reveal many traces of water-lillies and hearts, found often in combination with images of lions.
15th century books on heraldry show that two armorial bearings were derived from the early ones: a coat of arms showing lions and seven pompeblêdden transformed into little blocks, the other being the arms with the seven now known lillies on stripes.