What is the name of Christian religious groups whose members traveled outside of the United States to regions and nations such as the Middle East in 1819, Hawaii in 1820, and China in 1830?

Missionary

Explanation:

The members of religious groups who are sent to different regions to promote their faith and others services like education, healthcare, economic development and health care. The term originated in 1598 and the first missionaries were the Jesuits.

According a study conducted in 1970 there were 240, 000 christian missionaries across the world. This number grew and in 2000 there were 440,000 missionaries.  

The first missionaries in USA arrived on March 30, 1820 on a ship called the Thaddeus. The first missionary in china was Robert Morrison , he was sent by London Missionary society in 1807. He was a protestant.

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