Introduction
Manasseh is the elder son of Joseph and Asenath. Jacob, near the end of his life, formally adopted both Manasseh and his brother Ephraim as his own sons, "as Reuben and Simeon are mine", placing them on the same footing as his own twelve sons and thereby making them, rather than Joseph directly, the ancestral figures of two half-tribes of Israel.
This article follows the biblical account in Genesis. Where later Jewish, Christian or Islamic tradition adds detail not found in the text itself, the article identifies it as such.
Family
Birth and naming
Joseph named his firstborn son Manasseh, explaining, according to Genesis 41:51, that "God has made me forget all my hardship and all my father's house", a name reflecting Joseph's complex feelings about his past suffering and separation from his family.
Jacob's adoption and blessing
When Jacob was near death in Egypt, he formally adopted Manasseh and Ephraim as his own sons, entitled to full inheritance shares alongside his other twelve sons, a decision that structurally splits the later tribe of Joseph into two half-tribes. When Jacob then blessed the two boys, he deliberately crossed his hands to place his right hand, signifying the greater blessing, on the younger Ephraim rather than the elder Manasseh, despite Joseph's attempt to correct him; Jacob insisted this was intentional, saying the younger brother would become greater, though Manasseh too would become a great people.