1)Though Nathaniel Hawthorne's ancestors were Puritans, he did not share Puritan beliefs and values, and wrote the Scarlet Letter to denounce those values.
Puritans believed in a theocracy where the church and state are combined into one. This later proved illogical as it interfered with civil rights and essentially one's independence. Puritans were also a very judgmental people, who enjoyed public exposure of sins and those who disagreed with their beliefs. Hawthorne portrayed this aspect of Puritanism by constantly exposing Hester to public condemnation for her sin of adultery and by putting her on the scaffold to humiliate her in front of the townspeople. Those who didn't agree with the Puritan lifestyle were kicked out of society or looked down upon, just as Hester was throughout the novel. They also took pride in a joyless, non-sexual life, which is another reason why Hester was continuously disgraced for being different from them.
Hawthorne despised Puritanism. He felt that Puritans were hypocritical because they came to America looking for religious freedom, yet did not give it to others. He believed that in God's eyes the unpardonable sin was invading privacy, something that Puritans took to an extreme. In a Puritan society, it was rare for something to be kept secret or private. He also believed that Puritans viewed life in a black and white perspective; there was no gray area in between. Either something was right or wrong; there was no other explanation. Hawthorne stressed and admired personal independence, something that he would never have done if he had believed in the Puritan values of his ancestors.
3) Hawthorne chose to revolve The Scarlet Letter around one very powerful character that he deeply admired, Hester Prynne. He admired this character for her strong will and strength to uphold her own beliefs...