I'm not a follower of islam, my best friend is.
She works as a model in India and has dated guys of all religious backgrounds.
Her sect is liberal shia, accepts interfaith marriage for men & women and her parents have always welcomed all their children's friends.
Guys belonging to the same islamic sect and others are almost always put off by her dietary allergy fearing it will be a hereditary problem.
The orthodox Judaism and Christianity of the ancient era firmly prescribed religious endogamy- for both men and women.
Plenty of scriptural quotes containing rather blunt admonitions against marriage to anyone outside of the religion (atheists, pagans or members of other religions).
Within traditionalist christianity converts were generally welcomed but "unbelievers" were despised and generally widely disparaged in the preachings of religious leaders.
Internal marriage requirements serving to promote a long tradition of raising children in compliance with ancient books of scripture and an insular mentality amongst the congregation.
Plus highlighting the openly hostile, separatist and xenophobic "one true religion" religious supremacy agenda for centuries.
However in almost all religions there have always been those willing to divert from the ancient orthodoxy; for love, money, political reasons or to build a healthy family dynasty.
Sometimes with the approval of shrewd religious leaders hoping that an interfaith marriage could pave the way for an eye-wateringly large donation or mass religious conversions.
One example of the latter being the establishment of Christianity in England following the interfaith marriage of the Frankish princess Bertha and pagan Anglo-Saxon ruler Æthelberht of Kent during the 6th century.
I support interfaith marriage.
My mother is a conservative catholic from an ultra-traditionalist family with a tradition of cousin marriages and my father is a loud militant atheist.
Even today, many followers of orthodox judaism will not marry a member of another religion, unless they undertake an orthodox compliant conversion.
All fundamentalist christians decide between either marrying fellow fundamentalist christians, converts to fundamentalist christianity or remaining unmarried and celibate.
Same applies to members of the orthodox church, which welcomes converts but forbids marriage with members of other christian sects or religions.
Many conservative protestant and non-denominational churches strongly advise members not to marry people who are not practising christians.
Catholics have been allowed to marry atheists & members of all other religions since the 20th century postwar vatican ii reforms- as long as neither is divorced and the couple make wedding vows promising to raise their future children as catholics.
In theory, the children are supposed to choose whether they wish to undertake the sacrament of catholic confirmation as adolescents.
Although in practice, a young person refusing to be confirmed as catholic risks generating a lot of anger from a conservative catholic parent and is subjected to a lot of pressure to comply with the religious traditions.