The peace he found with the U.S. was short-lived. The boom in the gold rush brought whites to the Apache lands in search of the shiny rocks. Mangas tried to peacefully remove the miners from his land, promising to take them to more lucrative spots, but the miners didn't trust him. They stayed put, and eventually their polluting Apache waters and driving off Apache game led Mangas to unite the Apache bands. His daughters were given to other leaders in marriage, one most notably to Cochise. Known for his wisdom, Mangas was a firm believer the Apache bands must stick together to dismantle the threat of the U.S. or Mexico overtaking the Apache way of life.
Mangas and Cochise joined forces and led the way for what is now known as the Apache wars. Their intent was to drive all Americans off Apache lands. Mangas was captured in January of 1863 by captain Edmond Shirland's First California Volunteer Cavalry. He was taken to Fort McLean in Arizona and later killed by his guards. Most of his remains were destroyed by the white man. Among his people in today's society, he is remembered as a great leader who strove for peace.