Wickham was shipped to a regiment in the North because the army was stationed there.
There's no specific mention of why the regiment was in the North in the novel. However, it's important to remember a few things about the British Army at the time:
* Military Presence: The British military was stationed in various locations around the country, including the North.
* The Threat of Napoleonic Wars: Though the Napoleonic Wars didn't begin until 1803, the threat of war with France was already present during the time period of *Pride and Prejudice* (around 1811). The army would have been strategically deployed to prepare for potential conflict.
* Military Duties: The army had various responsibilities, including maintaining order, protecting borders, and responding to any potential uprisings.
While the specific reason for Wickham's regiment being in the North is never explicitly stated in the novel, it's safe to assume it was due to general military deployments and the need for troops to be stationed in various parts of the country.