Guillaume Châteaubriand III de La Guerche, Lord of La Guerche, Lord of Pouancé, Lord of Segré, was born circa 1190 to Geoffroi III de La Guerche (1170-1195) and Louise de Château-Gontier and died 4 September 1223 of unspecified causes. He married Hersende de Sillé (1190-) 1206 JL .
Children
| Name | Birth | Death | Joined with |
| Elisabeth de La Guerche (1210-c1257) | 1210 | 1257 | Pierre de Chemillé (1204-1248) |
| Guillaume IV de La Guerche (1215-1271) | 1215 | 1271 | Anne de Montmorency (c1219-c1266) |
| Thomasse de La Guerche (1219-) | |||
| Geoffroi IV de La Guerche (1220-1264) | |||
| Sibylle de La Guerche (1221-1251) | |||
Residences
Footnotes (including sources)
| ‡ General |
| Ω Birth |
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