Mechthild von Sayn

Countess Mechthild of Sayn (c. 1203 – c. 1291), also called Mechthild of Landsberg, Mechtild, Mechtildis or Mathilde, was the wife of Henry III of Sayn. She was an important figure in the Late Middle Ages because of her religious foundations (Stiftungen).

Life Mechthild was the daughter of Margrave Dietrich of Landsberg, son of Dedi the Fat, and Jutta, daughter and heiress of the Thuringian landgrave, Louis III Mechthild was born around 1200, according to other sources around 1203, and around 1215 she married Count Henry III of Sayn. In a deed at Heisterbach Abbey dating to 1216, Mechthild is described as Henry's wife. The trigger for the marriage was a dispute between Dietrich of Landsberg and Henry II of Sayn, whose territories bordered one another. In addition the two were on opposing sides in the German throne dispute at the end of the 12th century. Dietrich, a supporter of the House of Hohenstaufen, owned Altenwied Castle, built by his ancestors; Henry II was for the House of Welf, and built the Löwenburg. In 1205, Pope Innocent III asked whether the dispute could be settled by a marriage between Henry III and Mechthild. The agreement must have taken place no later than 1207, since Dietrich of Landsberg died that year.

Henry had had his will drawn up at Blankenheim Castle in the presence of the abbots of Marienstatt and Heisterbach during Christmas week of 1246. He decreed that if his unborn child survived, Mechthild should become the sole heir. But if the child died, then Mechthild should have the right to keep all goods until her death, after her death the estate was to pass to the children of Henry's sisters. Henry's sisters were Adelheid, who first married Godfrey of Sponheim-Starkenburg (died 1223?), her second marriage in 1225 was to Eberhard of Eberstein (died 1263?), and the younger Agnes, who married Henry of Blieskastel.