Baptist Churches
Baptists originated from 17th century English Puritanism. The term "Baptist" came from their insistence that baptism should be reserved for those old enough to comprehend and confess a personal faith in Jesus. Modern Baptists are a group of Christian denominations and churches who subscribe to a theology of believer's baptism (as opposed to infant baptism), salvation through faith alone, Scripture alone as the rule of faith and practice, and the autonomy of the local church. Churches in the Baptist family include the Southern Baptist Convention, the National Baptist Convention of America, and the American Baptist Churches in the USA.
Approximately 15.3% of Americans identify as Baptists, making the second largest religious group in the U.S., following Roman Catholics. The top states with Baptist adherents are Mississippi, Alabama, Arkansas, Tennessee and Kentucky.
General Baptist information: https://www.thearda.com/us-religion/group-profiles/families?F=96
Association of Association of Welcoming & Affirming Baptists: https://awab.org/
Featured books:
Baptists Through the Centuries by 
Baptists in North America by 