In 1240 Otto II Duke Guelders and Margaretha Cleves (age 22) were married. She by marriage Duchess Guelders. She the daughter of Dietrich Cleves V Count Cleves and Mathilda Dinslaken Countess Cleves. He the son of Gerard III Count Guelders and Margaret Reginar Countess Guelders. They were fourth cousins. He a great x 4 grandson of King William "Conqueror" I of England.

In 1253 Otto II Duke Guelders and Philippe Dammartin Countess Eu were married. She by marriage Duchess Guelders. She the daughter of Simon Dammartin and Marie Montgomery Countess Ponthieu. He the son of Gerard III Count Guelders and Margaret Reginar Countess Guelders. He a great x 4 grandson of King William "Conqueror" I of England.

In 1276 Reginald I Count Guelders (age 21) and Ermengarde Luxemburg I Duchess Limburg were married. She by marriage Duchess Guelders. She the daughter of Waleran Luxemburg IV Duke Limburg and Judith Kleve Duchess Limburg. He the son of Otto II Duke Guelders and Philippe Dammartin Countess Eu. They were fourth cousins. He a great x 5 grandson of King William "Conqueror" I of England.

In 1286 Reginald I Count Guelders (age 31) and Margaret Dampierre Duchess Gueders (age 14) were married. She by marriage Duchess Guelders. She the daughter of Guy Dampierre Count Flanders (age 60) and Isabelle Luxemburg Countess Flanders (age 39). He the son of Otto II Duke Guelders and Philippe Dammartin Countess Eu. They were half third cousin once removed. He a great x 5 grandson of King William "Conqueror" I of England. She a great x 5 granddaughter of King William "Conqueror" I of England.

In May 1332 Reginald "Black" II Duke Guelders (age 37) and Eleanor of Woodstock Plantagenet (age 13) were married at Nijmegen [Map]. She by marriage Duchess Guelders. His second marriage; he had four daughters from his first marriage. He subsequently sent her from court to Deventer Abbey [Map] in 1336 under the pretext that she had leprosy. He subsequently tried to annul the marriage but she contested the annulment by proving she wasn't a leper. The difference in their ages was 23 years. She the daughter of King Edward II of England and Isabella of France Queen Consort England (age 37). He the son of Reginald I Count Guelders and Margaret Dampierre Duchess Gueders. They were second cousin once removed.

In 1379 William Jülich 3rd Duke Guelders 3rd Duke Jülich (age 14) and Katherine Wittelsbach Duchess Guelders (age 17) were married. She by marriage Duchess Guelders, Duchess Guelders. She the daughter of Albert Wittelsbach I Duke Bavaria (age 42) and Margaret Silesia. He the son of William Jülich I Duke Jülich (age 52) and Marie Guelders Duchess Jülich. They were fourth cousins. She a great x 5 granddaughter of King Henry "Curtmantle" II of England.

On 05 May 1405 Reinald Jülich 4th Duke Guelders 3rd Duke Jülich (age 40) and Marie Harcourt Duchess Guelders were married. She by marriage Duchess Guelders, Duchess Guelders. She the daughter of John Harcourt VI Count Harcourt. He the son of William Jülich I Duke Jülich and Marie Guelders Duchess Jülich.

In 1463 Adolf Egmont 2nd Duke Guelders (age 24) and Catherine Bourbon Duchess Guelders (age 23) were married. She by marriage Duchess Guelders. She the daughter of Charles Bourbon I Duke Bourbon and Agnes Valois Duchess Bourbon (age 58). He the son of Arnold Egmont 1st Duke Guelders (age 52) and Catherine La Marck (age 45). They were first cousin once removed. She a great x 5 granddaughter of King Edward "Longshanks" I of England.