Short answers, pulled from the story.
A billet became a legal instrument that forced civilians to open their doors to soldiers. This document evolved from a polite invitation into a command that could uproot families and shatter domestic peace. The term began as a billet of invitation but the reality of its application turned hospitality into a legal obligation.
Repeated petitions against this practice culminated in its outlawing in 1689 as an extension of a section of the Petition of Right 1628. This historical pivot point marked the moment when the state acknowledged that the private home was a sanctuary that the military could not simply occupy without consent. The evolution of the word from a polite note to a coercive order reflects the shifting balance of power between the individual and the state during the early modern period.
The American colonists viewed the quartering of soldiers in civilian homes as one of the most egregious abuses of power committed by the British government. This specific resentment led to the creation of the Third Amendment to the United States Constitution which provides strict restrictions on the manner in which the federal government may require civilians to provide housing for American soldiers. The legacy of this conflict remains embedded in the American legal framework ensuring that the concept of a billet as a private dwelling remains a point of contention rather than a standard practice.
During the darkest days of World War II the term billet took on a new meaning as civilians who had been evacuated from cities in danger of attack were billeted in communal shelters or in the homes of individuals. The practice of billeting evacuees was widespread in Britain during the Blitz particularly when children and other non-essential persons in major cities were sent to rural areas for safety. The number indicating the location of the quarters would be specified on the billet a detail that became crucial for organizing the massive displacement of people.
In the United States Navy the Marine Corps and the Coast Guard the word billet has evolved to mean a specific personnel position assignment or duty station which may be filled by one person. Every person reporting aboard a ship or shore installation in the naval services is assigned a billet according to the unit watch quarter and station bill which shows the duties stations and billet assignments for all crew members. The term has moved far beyond the physical space of a barracks to define the very identity of a service member within the chain of command.
In North America billet families offer room and board to junior ice hockey players who leave home to join elite teams in other towns creating a unique social arrangement that blends sports with domestic life. Coaches are often involved with matching a player to a billet family and the objective is to provide a home away from home for young players during the season. Fears over child safety in amateur sports in Canada drastically curtailed billeting practice leading many places to stop the practice entirely.