In 2010, 62 million people serve as volunteers, according to U.S. government statistics. Why do American people do? The roots of U.S. volunteerism are far reaching and deep. Americans help each other since colonial times because their priority is survival (Physically, the land was a wilderness) Farmers pioneered the land and built barn and harvest together in neighborhood. And some church made as volunteer. In 1976, Benjamin Franklin formally organized Philadelphia’s volunteer fire company.　350 years later volunteerism imbues American society. The role of volunteer was pioneer. Does this sound natural?

In 2010, 62 million people served as volunteers, according to U.S. government statistics.
Why do Americans do so?
The roots of U.S. volunteerism are far reaching and deep. (ok!!)
Americans had been helping each other since colonial times because their priority is survival (Physically, the land was a wilderness).  Farmers pioneered the land and built barns and harvest together in the neighborhood.
And some church made as volunteer. (Sorry I don't understand what you wish to convey here)
In 1976, Benjamin Franklin formally organized Philadelphia’s volunteer fire company.
As such, 350 years later volunteerism is imbued in to American society.
The role of volunteer was pioneer. (Sorry I'm not sure what you wish to convey here as well).