Charlotte's narrative is set in 1832, a significant year for England. This is the year in which the Reform Act of 1832 was passed there (also known as The Representation of the People Act 1832). This legislation changed the UK's electoral system to give representation to many who had otherwise not been represented, a victory for England's fervent reformers.
Aside from the actual legislation that was being passed, the nineteenth century can be more broadly characterized as a time of social change and upheaval. The abolition movement was in full swing. Slavery and the slave trade had been abolished in England by 1807, though was still flourishing in America. Women's rights were also a prominent topic of debate, with many feminist writers bringing up questions about gender inequalities. (Mary Wollstonecraft's A Vindication of the Rights of Women, published in 1792, is an example of one of the first fiery opinion pieces written on this subject.) The Industrial Revolution ensured that class inequality was a part of public discourse, with writers such as Charles Dickens penning the terrible conditions suffered by the poor.
The novel spans the Atlantic Ocean, between England and America, and because of this we would call The True Confessions of Charlotte Doyle a transatlantic (across the Atlantic) novel. The ship's crossing of the Atlantic Ocean is important because the journey calls our attention to other things that crossed the Atlantic too: cargo, goods, and most importantly, slaves. Charlotte is American, and her father is a cotton manufacturer. Again, the association with slavery is implied, as cotton was a crop that depended upon slave labor, especially in the American South.
Charlotte's destination is Providence, Rhode Island. Rhode Island is significant because it's one of the only American states, as Zachariah tells us, where slaves are free in 1832 (17.42). America would then seem to be a place of increased freedom. At least, Charlotte appears to think so: "America, where, so I had been long taught to believe, greater freedom held sway" (20.81). But does Charlotte's optimism about America prove to be true? What do the events of the novel suggest?