When Atticus went to Montgomery "to read law," what tradition was broken according to the narrative of To Kill a Mockingbird?
Atticus's study of law in Montgomery broke the long Finch tradition of men staying on the land to farm cotton. The family's ancestor, Simon, a fur-trapping apothecary from Cornwall, had originally come to Alabama by way of Philadelphia, Jamaica, and Mobile. He bought a plot of land on the Alabama River forty miles from Saint Stephens, and, having forgotten what Scout refers to as "his teacher's dictums on the possession of human chattels," he purchases three slaves. This phrase is a reference to John Wesley's opposition to slavery. Wesley was the founder of Methodism and a fervent opponent of slavery, but although Simon Finch was a Methodist, he purchased slaves.
After the Civil War, the Finches lost most of their wealth, including their slaves, but retained their land. The family lived on the land well into the 20th century, when Atticus went to Montgomery to study law and his brother, Jack, studied medicine in Boston. Their sister, Alexandra, stayed at Finch's Landing and was married. Atticus and Jack break with the family tradition of living as cotton farmers, and they have other experiences that make them different from most of the people in the area.
When Atticus Finch left Finch Landing for Montgomery in order to study law while his younger brother Jack went to Boston to study medicine, the tradition of male Finches living on Finch's Landing was broken. Only their sister Alexandra remained there.
Scout narrates that her Aunt Alexandra married a rather phlegmatic man, who mostly lay in his hammock by the river watching his trout-lines, quite unlike the ancestral patriarch of the family, Simon Finch, "a fur-trapping apothecary" from Cornwall, England.
Simon Finch came to America because of religious persecution. First, he came across the Alantic Ocean to Philadelphia, then down the Atlantic all the way to Jamaica in the Caribbean Sea and on up to Mobile, Alabama, on the Gulf of Mexico. From there, he wandered in a northerly direction from Mobile on the Alabama River about forty miles from the old Spanish settlement of St. Stephens. At this location he established a homestead on the banks of the river, a location nearly forty miles from St. Stephens, in which he had found a bride.