Constantia Eriksdotter (1560-1649) was the illegitimate daughter of Eric XIV of Sweden and Agda Persdotter. She married the nobleman Henrik Frankelin (d. 1610) in 1594. She was called "The Queen of Tiveden".
Constantia Eriksdotter and her sister Virginia were removed from their mother's custody when she married in 1561. This was illegal, as according to the law the mother had sole custody until the children reached the age of three. They were placed first in the court of Princess Cecilia of Sweden, then that of Princess Elizabeth of Sweden (1564), and finally that of queen Karin Månsdotter. In 1573, she visited her deposed father in prison, and was possibly the last family member to see him alive.
On 13 January 1594, she married the English nobleman Henry Frankelin, courtier to her uncle Charles IX of Sweden. The same year, she was awarded nine estates in Väne parish in Bohuslän by her cousin king Sigismund III Vasa. In 1595, she was further granted Bocksjö Manor in Tiveden in Västergötland, where she chose to reside. As a widow after 1610, she mainly lived at Odenfors Manor outside Vreta. Like her father, Eric XIV, Constantia was described as mentally fragile. In the Undenäs church, a moonstone belonging to Constantia is still kept.
Carl Frankelin (d. 1631), major, fell at Greifswald when occupied under the Treaty of Stettin.
Maria Catharina Frankelin (d. 1661), married to governor and nobleman Anders Koskull (1594-1676)
Elisabet Frankelin (d. 1655), married to Christian Frost (d. 1631)