The name Manasseh means forget, as his father Joseph was forgetting his trouble in Egypt at the birth of this son. Americans, unlike nearly every other nation on earth, have no memory of their own history. This is why.
At the birth of Manasseh his father named him to mark the fact that the joy of having a son was causing him to forget his troubles in Egypt.
1 Genesis 41:51
51And Joseph called the name of his firstborn Manasseh; For God, he said, has made me forget all my troubles, and all my father's house.
The expression house when used in the personal sense means litterally family. Joseph was missing his family and the birth of this son was comforting him. In a national sense the word house implies nation. Americans are particularly inept at remembering their roots in other countries. Some families take special care to maintain contacts with family members in the "old country" but for most the focus is simply on the present state of the country.
There was a widespread attempt to disconnect families from roots in other countries. This happened even with the changes in the spelling of names and because of the great distances back to home nations across the oceans.
When I first share this material with groups I often get the objection that the nation has no history before the 1770s and cannot be a people group that is any older. This objection is yet another reflection of this false American belief about not having any roots anywhere earlier in history. God is in the business of raising the dead and he did so with this very ancient tribe, as old as any of the others recorded in the Bible.
The name "Forget" which is what Manasseh means has several specific uses that matter to tracking references to Manasseh in scripture. The best is an important reference that warns that when wealth accumulates we as people will forget what God has done.
5 Deuteronomy 6:6-12
6And these words which I command you this day will be in your heart;
7and you will repeat them diligently to your children, and will talk of them when you sit in your house and when you walk by the way and when you lie down and when you rise up.
8And you will bind them for a sign on your hand, and they will be as a token between your eyes.
9And you will write them on the doorposts of your house and on your gates.
10And it will be, when Yahvah your God will have brought you into the land which he swore to your fathers, to Abraham, to Isaac, and to Jacob, to give you great and attractive cities, which you did not build,
11and houses full of all good things, which you did not fill, and cisterns dug, which you did not dig, and vineyards and olive trees, which you did not plant; when you will eat and be full;
12then be careful lest you forget Yahvah your God, who brought you forth out of the land of Egypt, from the house of servitude.