Basically sectionalism is the idea of "different sections" of a country/state will have different lifestyles.
For example: In the past the North (United States) was based off of industry and also known as the "bread basket" whereas the South had plantations and slaves, a more agricultural lifestyle compared to teh north.
English-speaking British colonies in North America – the conflict is known as the French and Indian War. In English-speaking Canada – the balance of Britain's former North American colonies – it is called the Seven Years' War