I think it was the Spanish.
to convert native Americans to Christianity.
Local tribes were relocated and conscripted into forced labor on the mission.
"Mission Indians" describe the tribes that were heavly involved with Catholic Missions - mostly in the California area.
the California native Americans who were brought to the building site were forced to build the missions
The Indigenous peoples of the Americas, particularly various tribes in present-day California and the Southwestern United States, were forced to work as slaves for Spanish missions. The Spanish colonizers sought to convert Indigenous populations to Christianity and exploit their labor for agricultural and other economic activities. This system often resulted in harsh treatment and significant population decline due to disease and overwork.
The Mission system was a virtual slavery. The Indians were forced to work for the Missions & land owners in the area.
the California native Americans who were brought to the building site were forced to build the missions
where can you find information about california missions
The duration of The Missions of California is 3600.0 seconds.
In California, a total of 21 Missions were built. See link:
Serra Established Missions Through California.
The Missions of California was created on 2007-04-10.