See John J. Delaney: Dictionary of Saints, pp. 83-84.
See internet site for ancestors of Charlemagne:
ghg.net/shetler/oldimp/208.html
After her husband Ansigesil died in 1691, St. Begga built a church and convent at Ardenne, France, on the Meuse River, where she died. December 17, 693.