Hedwig of Silesia died on 1243-10-15.
Hedwig of Silesia was born in 1174.
Harry found Hedwig's name in A History of Magic. The book does not tell us who Hedwig (the witch) was, though Hedwig is generally a German name, so she might have been a German witch of some historical significance. JK Rowling probably choose Hedwig's name based on Saint Hedwig (Duchess of Silesia).
Beatrice of Silesia died in 1322.
Hedwig Dohm died in 1919.
Hedwig of Nordgau died in 993.
Hedwig Borzecka died in 1906.
Hedwig Lachmann died in 1918.
Hedwig Pringsheim died in 1942.
Hedwig Raabe died in 1905.
Hedwig of Holstein died in 1324.
Hedwig Dransfeld died in 1925.
Hedwig Weitzel died in 1971.