Biblical figures intermarrying with neighboring nobility?

In answer to the video "How Islam Shaped Its Sources"

Hagar, the legitimate wife of Abraham who gave birth to his legitimate son Ishmael, the "only son" who would later be taken for sacrifice to God, was the princess daughter of an Egytpian King according to even some Rabbinical traditions. As a side note it is interesting to note that David's great grandmother, Ruth, was a Moabite princess that preferred converting to Judaism and live as an ordinary member of the comunity. Her piety and good manners were well known, a book of the biblical cannon is named after her. Solomon became allied to the Egyptian king through marrying his princess daughter 1Kings3:1, just like Abraham, and loved her more than his other numerous wives 1Kings11. There are other such recorded unions, between Israelites and daughters of Egyptian nobility 1Chr4:18. 

In the Jewish encyclopedia, we read something even more interesting;

"While the two narratives, Gen. xvi. and xxi. 9-21, are not directly contradictory, the critical school, pointing to the fact that in both instances Hagar is expelled upon Sarah's request and with the reluctant assent of Abraham, and that in both instances she receives, while sitting by a fountain, a divine message foretelling the great destiny of her son, finds in these narratives two parallel accounts of the origin of the Bedouins, whose racial affinity with the Israelites the latter had to admit, while degrading them by tracing their origin to a concubine of their common ancestor"