Together, the influence of the Muslim merchants and the fortunes of Islam made rapid advances following this favorable change. By the late 16th century, conversion was a routine event. Although the Cham royalty remained Hindu until about 1607, they encouraged conversion to Islam among their nobility for commercial reasons. The kingdom had been made into a Vietnamese vassal by 1611. This change resulted in no perceptible negative impact on the Middle Eastern Muslim influence or Islam’s popularity. By 1670s, the bulk of the population and the Cham royalty itself was Muslim.