Could you please help decipher this comment regarding To Kill A Mockingbird and The Scarlet Letter?
"Harper Lee doubtless could write about her fiction what Nathaniel Hawthorne wrote of The Scarlet Letter, that the events of those years in which the work was conceived had a decided effect on the novel itself."
This comment simply means that both Harper Lee and Nathaniel Hawthorne were impacted by the things that were really happening in their societies and personal histories and included many of these elements in their novels.
Lee's To Kill a Mockingbird, for example, is set in Alabama in the 1930s and includes a storyline similar to one which actually happened in the 1930s, at the time Harper Lee was writing her novel. The Scotsboro Trials were set in Alabama and were full of nearly all of the same prejudices and ugliness which Lee portrays in the novel (see link below).
Racism is still a significant part of the South at that time, and a black man accused of any crime against a white person would have been a near-certain death sentence for the black man. A black man accused of a sexual crime against a white woman had no chance of escaping guilt, and that is exactly what happened in both the Scotsboro trials and Tom Robinson's trial. Jurors were primarily white men (though it was legal for them to do so, women were not generally allowed to serve) who had nothing to lose by being on a jury; unfortunately, these men were also among the most uneducated and racist men to be found.
While there were certainly some people in Alabama who were not prejudiced against blacks (such as Atticus and Miss Maudie), most people still believed blacks were inferior and treated them that way. It was an awful time in the history of the South because while blacks were technically free, they were still enslaved by the practice of prejudice. Harper Lee was born in 1926 and grew up in this world, which is why it rings so true in her novel. As your quote states, "the events of those years in which the work was conceived had a decided effect on the novel itself." While she did not write Mockingbird until the 1950s, these experiences and her own life experiences during this time shaped this novel.
The same is true of Nathaniel Hawthorne. The Scarlet Letter is set in Salem, Massachusetts, in the 1640s; though the novel was not published until 1850, Hawthorne writes about some things he lived, in a way. Hawthorne grew up in Salem, the site of the infamous witch trials in the 1690s; even worse, he was related to the only judge who never repented for his participation in the trials (which is why Hawthorne changed the spelling of his name to differentiate himself from that Hathorne). Hawthorne always felt guilt for this connection, and in his novel he depicts a Puritan world which is the forerunner of those events.
The point of Hawthorne’s text, like several of his earlier short stories, is to question if not outright criticize the severity of the Puritan law and the self-righteous intolerance of the Puritan community. Like other authors of his day, Hawthorne uses seventeenth century Puritanism as a point of departure for reflecting on what a Christian community should strive for in the nineteenth century.
His struggles with what religion should mean and be in his own time lead him directly to early American Puritanism and his own history.
Both of these authors wrote their novels, to a great degree, based on what they knew, including their personal experiences in life and the environments and times in which they lived. That authenticity is one of the reasons both novels are considered classics.