Margret(h)e is an alternate spelling of the feminine given name Margaret.
People so named include:
Margrete or Margaret I of Denmark (1353–1412), Queen of Denmark and Queen of Norway and Sweden by marriageMargrethe II of Denmark (born 1940), queen regnant of DenmarkMargaret of Sweden, Queen of Norway or Margrete Eriksdotter (c. 1155–1209), queen consort of NorwayMargrét Skúladóttir (1208–1270), queen consort of Haakon IV of NorwayPrincess Margaret of Denmark (1895–1992)Margrete Auken (born 1945), Danish politicianMargrete Aamot Øverland (1913–1978), journalist and member of the Norwegian Resistance during World War IIMargrethe Lasson (1659–1758), first novelist in DenmarkMargrethe Munthe (1860–1931), Norwegian teacher, children's writer, songwriter and playwrightMargrethe Schall (1775–1852), Danish ballerinaMargrethe Vestager (born 1968), Danish politician