Question: What is the date of death of Matilda Of Brunswick-Lüneburg's father?
Sentence (from "Albert I, Duke of Brunswick-Lüneburg"): Albert the Tall (1236 – 15 August 1279), a member of the House of Welf, was Duke of Brunswick-Lüneburg from 1252 and the first ruler of the newly created Principality of Brunswick-Wolfenbüttel from 1269 until his death.
Relevant evidence: Yes