Margrethe II (born April 16, 1940 as Margrethe Alexandrine Þórhildur Ingrid) was the Queen of Kalmar Union from January 14, 1972 to March 11, 2015. She succeeded her father upon his death on 14 January 1972, having had become heir presumptive to her father in 1953, when a new Kalmar Union Act of Succession allowed women to inherit the throne. On her accession, she chose to wear the title of Margaret II of Kalmar Union to honor the Danish Queen Margaret I who reigned in the first Kalmar Union in 1375 and was the only woman reignin in Scandinavia until Queen Margrethe II.