BEIRUT — Reem Kaedbey was never very religious. She's not even sure there is a God.

But when it came to marriage, she never had any doubt she would choose within her family's sect, a tiny offshoot of Shiite Islam known as the Druze faith.

“It's a requirement for my parents,” said 28-year-old Kaedbey, who lives near Beirut and works for the United Nations. “I didn't want to get into problems.”

Finding a life partner is hard enough for anybody. Members of the Druze faith face an added pressure: keeping the religion alive.

The faith is thought to have about 1.5 million members, with most living in Lebanon, where they make up 5 percent of the population, and Syria, where they make up 3 percent. But an exodus of people fleeing wars in those countries has fueled a small but growing diaspora. There are about 30,000 in the United States, with the largest concentration in Southern California.

While the Internet has made it easier for Druze to connect with each other — Kaedey met her husband on social media — growing contact with the outside world has increased the chances that members will marry outside the faith. That is a path to extinction, because the religion does not accept converts and in its more conservative strands reject children of mixed marriages.

“In the modern day, there's a lot more tolerance and acceptance, but for the ones who truly follow the faith, once a person marries a non-Druze, they took the decision of leaving the faith,” said Daniel Halabi, a 22-year-old sheik, or religious leader, who lives in Chicago. “The religious laws are clear.”

And so the future of the Druze faith may depend not only on pairing up its youth — a community effort — but also on whether the religion itself can make accommodations to the modern world.

As religions go, the Druze faith is not especially old, having been formed roughly 1,000 years ago. It accepted the prophets of Islam and Christianity and incorporated elements of Greek philosophy and Gnosticism.

Unlike other forms of Islam, it embraced reincarnation, allowed women to become religious leaders, banned men from having multiple wives and did not mandate prayer at set times or places.

Its most important early promoter was Al Hakim bi-Amrillah, the sixth leader of the Fatimid Caliphate that spanned a large area of North Africa and the Middle East and had its capital in Cairo. After his mysterious disappearance, his followers in Egypt were exterminated.

But they survived in other areas of the Middle East, including in present-day Lebanon and Syria.

In 1044, after a brief period of proselytization, the faith was closed to converts. Early Druze communities were insular and isolated and left historians with few records.

The religious texts have never been widely disseminated, leaving it to the sheiks to educate adherents on the finer points of the faith.

The diaspora began as a trickle and picked up in 1975 with the beginning of Lebanon's 15-year civil war. The country's 2006 war with Israel spurred more to leave, and most recently, many Druze have joined the stream of refugees from Syria's civil war.

As Druze members have branched out, many have lost touch with the religion, raising existential questions about its future.

“Very few of them have an in-depth understanding of their dogmas,” said Chad Kassem Radwan, an anthropologist of Lebanese Druze descent who wrote a doctoral dissertation for the University of South Florida on Druze identity in Lebanon. “How do you preserve your heritage? This is truly the seminal issue of the Druze community.”