Two entries with the name Blancheflor.
Blancheflor
Blanchefleur, Blanscheflur, Blanschflur
In Gottfried, mother of Tristan and sister of King Mark of Cornwall.
She fell in love with King Rivalin of Parmenie when he came to Cornwall to assist Mark against Ireland. Rivalin fell deathly ill of a painful wound, but the sight and affections of Blancheflor cured him and the two were married. She died giving birth to Tristan on the same day that Rivalin was slain.
Called Blesinbil in the Norse version of the legend, her character is replaced in later stories by Elyabel.
Sources
Tristrant | Eilhart von Oberge, 1170-1190
Tristan | Gottfried von Strassburg, early 13th century
Sir Tristrem | c. 1300
Blancheflor
The daughter of King Triamour of Wales.
A giant named Urgan attacked her father for the right to possess her, but the giant was slain by Tristan.
Source
Sir Tristrem | c. 1300