For decades, political and economic upheaval in Southeast Asia separated ethnic Vietnamese communities in the United States from those in Asia, as their lives followed radically divergent trajectories.

Fourteen years ago, however, new ties were forged when a widely aired documentary revealed cases of child prostitution in ethnic Vietnamese neighbourhoods on the outskirts of Phnom Penh.

Outraged Catholic Vietnamese in the US began organising charity for their brethren in the Kingdom, connecting the two communities once again.

In a new report in the journal Migration, Transnationalism, and Catholicism, California State University’s Thien-Huong Ninh argues that this reconnection between “co-ethnic and co-religionist” counterparts demonstrates how religion can “revive and reconstruct” cross-national ethnic bonds, even in third-party countries where they’ve never existed.

While Vietnamese immigrants in the US slowly forged ties with communities in their homeland after the Vietnam War, Vietnamese Catholics in Cambodia lacked the resources to build similar relationships, Ninh writes. For years, Cambodia’s Vietnamese Catholics were isolated from communities outside of the Kingdom that shared their ethnicity and religion.

That changed in 2004 when Vietnamese churches began forming non-profits and gaining access to the Kingdom. While the groups provide humanitarian support for the general population, much of their efforts are directed towards the ethnic Vietnamese population.

The Franciscan Charity of San Francisco, which helps disabled orphans in Cambodia, is one such organisation. The group provides rice, clothing, medicine and other supplies to poor Vietnamese Catholics in Cambodia.

Another organisation is the De La Salle Brother’s Mission, which built a preschool near a Catholic Vietnamese village.

“Today, Vietnamese Catholics in the USA have become the forefront of this movement to assist ethnic Vietnamese in Cambodia,” Ninh writes.

While the exact number of Vietnamese Catholics in Cambodia is unknown, the population is estimated to be about 22,000. Traditionally, ethnic Vietnamese made up around 95 percent of Cambodia’s Catholic population. Today, however, they are estimated to constitute just two-thirds of Cambodia’s Catholics, thanks in large part to the Catholic Church’s efforts to convert ethnic Khmers.

According to Ninh, Vietnamese-American groups have a tense relationship with the Catholic Church of Phnom Penh, which is allegedly pursuing a policy of Khmerisation. Consequently, the organisations tend to work in remote areas away from the capital.

“Franciscan Charity and DLS have been working almost completely independent of the church hierarchy in Cambodia, which has perceived their presence as a threat to the church’s policies of ‘purifying’ the church of its overtly Vietnamese elements,” Ninh writes.

Phnom Penh’s bishop, Olivier Schmitthaeusler, however, denied that there are tensions between the church and Catholic Vietnamese organisations. Most of his congregation is ethnic Vietnamese, he says.

But Ly Sovanna, a communications officer for the Phnom Penh diocese, said the church is focusing its work on ethnic Khmer communities, and is preparing to baptise about 165 new converts this Easter.

“Young and old [Khmer] people are increasingly interested [in Catholicism],” he said. “We are now a Khmer Church.”

Still, he echoed the bishop’s claim that there are no tensions with the Vietnamese Catholics coming over from America.

“They are here, working in a few places,” he said. “They are serving communities, so we don’t have any problems with them.”