Under Malaysia’s system of constitutional monarchy system, each of the nine hereditary rulers is given a chance to be king for five years under a rotation system.

Observers say royal multicultural marriages have as much to do with the Southeast Asian nation’s colourful colonial history – which included Portuguese, Dutch and British colonialists – as well as the modern racial dynamics within the multicultural and multi-religious country.

But these unions, while largely accepted, have not been without controversy.

One of the earliest instances of the multicultural marriages was the 21st Johor Sultan, Abu Bakar, who married Cecilia Catherine Lange, the half-Balinese daughter of a Danish trader. The couple met in Singapore in 1870, fell in love and married – against the convention demanding racial purity back then.

Lange, who converted to Islam and became known as Zubaidah, had a son – Ibrahim of Johor, who was often described as an Anglophile. One of his wives was Scottish doctor Helen Bartholomew.

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Dating back to the colonial era (1824-1963) when then Malaya was part of the British Empire, Malaysian royals were encouraged to adopt British customs and traditions, according to Saad Salman, a Canadian journalist and self-described “royal watcher”.

“This led to some quite high-profile marriages between European women and some sultans and maharajas – which were discouraged by the colonial elites, but generally accepted by the population,” said Salman.

Westerners would have an easier time converting to Islam, said Aaron W. Hughes, a professor of Islamic studies at the University of Rochester. “In terms of Islam, it would be much easier for someone from the West since they would be familiar with the basic Judeo-Christian themes that Islam continues: God, creation, prophecy, the Day of Judgement, and so on,” he said. “A Buddhist or a Hindu, for example, would have a much more difficult time grasping such issues.”

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Under British rule, Malaysia’s ethnic groups were categorised under Malay, Chinese and Indian, a practice which continues till today. While Malaysian society adheres to tenets of multiculturalism, academics say the rigid divide between these groups have made intermarrying less common, especially among the elites.

“Despite such high levels of racialisation, many Malaysians – ordinary citizens, members of the political and economic elites, opposition politicians, religious leaders, intellectuals, artists and devotees of popular culture – claim to be anti-racist and are often critical of the prevalent racial assumptions. [But] the more honest and insightful among them … are worried by the hold of such racial assumptions over their own consciousness as well,” wrote the late scholar Joel S Kahn, in his article The Making and Unmaking of a Malay Race, in the 2005 International Journal of Social and Cultural Practice.

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Malaysia has long ties, particularly through colonialism, with Europe which have led to these marriages, said Salman. “But there are examples of Malaysian royals marrying people from other parts of Asia, the Americas, and Australia too.”

For example, there was the case of the 1981 marriage of Australian former ballet dancer-turned-reporter Jacqueline Pascarl to Malaysian royal Dato Raja Kamarul Bahrin of Terengganu state, which ended in divorce, and even led to charges of child abduction. Pascarl had accused the prince of taking their two children away from her.

As for the actual conversion process to Islam, Hughes the academic said the process was simple. “All one has to do is utter a statement saying that they believe that there is no god but God and that Muhammad is His messenger,” he said.

“Obviously they would have to say it with the proper intention for it to be valid. A non-Muslim can thus become a Muslim very easily. All they would need to do, at least in theory, is give up alcohol, pork, and begin to pray the requisite five times a day. If they wanted to learn Arabic to read the Koran and other texts, they could. But they do not have to.”

However, learning the nuances of the Malay-Muslim culture is a different story altogether, said Hughes. The foreign spouses would probably have a more difficult time learning the ins and outs of Malay culture, of which Islam is just one part.

Even for Meghan Markle, becoming the Duchess of Sussex resulted in a big lifestyle change for her, as there were many differences between American and British cultures despite the shared language, said Salman.

However, becoming a member of a Malay royal family calls for an even bigger change. “The biggest barrier would be language, despite many Malaysians speaking English, as it is instrumental in learning the culture and customs of a country,” he said.

“Looking at examples from the past, many foreigners have not been able to cope with the change, and some of the marriages between royals and foreigners have led to divorce,” said Salman. “However, there are many marriages that have proved to be a success, and there is no doubt that with some advice from their peers, and love and support from their spouse and new family, the newcomer will easily adjust into their new lifestyle.”