Biography
Mathilde von Jülich was born circa 1238 to Wilhelm IV. von Jülich (1210-1278) and Margaretha van Gelre (?-?) and died before 1279 of unspecified causes. She married Jan I van Loon (1230-1279) 1258 JL .
Children
| Name | Birth | Death | Joined with |
| Arnold V van Loon (1260-1323) | 1260 | 22 August 1323 | Marguerite de Vianden (-1316) |
| Lodewijk van Loon (?-?) | |||
| Willem van Loon (?-?) | |||