Marrying Jewish or Christian women
Answer:
Allah 
in the Holy Qur’an has said:
‘ (Made lawful for you) and chaste women from amongst the beleiveers, and chaste women from among those given the Book before you, provided you give them their dowers, binding yourself in marriage not going for lust, nor have paramours…. ’ (Surah Madinah v.5)
From the aforementioned verse the permissibility of marrying Christian or Jewish women can be derived. However, it should be borne in mind that if the women are Christian or Jews by name only and in reality are atheist then to marry them will be unlawful and haram.
Going back to your question, in the eyes of some Sahabas marrying Jewish or Christian women was not considered permissible. Someone asked Saaiduna Abdullah Ibn Umar 
whether it will be permissible to marry Christian women, he said the Holy Qur’an is clear: “ ‘Do not marry disbelieving women until they become Muslims’ – and I am not aware of a greater shirk than that of a person who openly declares Jesus as his Lord or God or Son of God.”
Another incident is when Saaiduna Hudhaifah Bin Yaman went to Madaain, he married a Jewish woman there. When Saaiduna Umar found out, he wrote a letter to him asking him to divorce the woman. Saaiduna Hudhaifah wrote back: ‘is she unlawful for me?’, in response Saaiduna Umar Radiallahu Anhu wrote ‘I am not saying that she is unlawful. But women from these people do not generally have chastity, therefore I apprehend immodesty finds entry into your home through this channel’.
Therefore, the Hanafi jurists have said that marriage conducted with a genuine Christian and Jewish woman is Makruh Tahrimi, however, the nikah will be valid. (Maariful Quran p.80-81 v.3)
Only Allah Knows Best
Mohammed Tosir Miah
Darul Ifta Birmingham.