Why did the new pharaoh not know Joseph in Exodus 1:8?
Egypt’s throne passed to a new line of kings. These rulers replaced the earlier pharaohs who had been friendly to the Israelites and had made agreements with Joseph. Because the new line had nothing to do with those old agreements, Joseph was not recognized or honored by them.
Les explains that the change was dynastic: a new king arose over Egypt after Israel had become fruitful, increased abundantly, and multiplied until the land was filled with them. Ancient history was unstable, and a line of kings could be overruled by newcomers who set up a whole new line. The previous pharaohs, from Joseph’s time, had been friendly to the Israelites while Jacob brought his children into Goshen. This new line, however, did not know Joseph and had nothing to do with the agreements the old pharaohs had made with Joseph and his offspring.
Now there arose up a new king over Egypt, which knew not Joseph.