Polygamy: Esau
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Genesis 26:34
When Esau was forty years old, he took as his wives Judith daughter of Beeri the Hittite and Basemath daughter of Elon the Hittite.
Genesis 28:9
Esau went to Ishmael and married Mahalath, the sister of Nebaioth and daughter of Abraham’s son Ishmael, in addition to the wives he already had.