Which Western European country did not develop a comprehensive set of rules at one time?

The choice of England as the answer highlights the country's unique legal development history compared to other nations in Western Europe. Unlike Germany, Sweden, and France, which often codified their laws into comprehensive legal systems, England's legal framework evolved through a combination of common law—a system based on court precedents—and statutes that were enacted over time.

This gradual development is characterized by the essentially case-based law system where legal principles were developed on a case-by-case basis rather than from a singular legislative code. This means that England lacked a comprehensive legal code established at one specific moment, contrasting with countries that underwent significant legal reforms to standardize and consolidate their legal systems into comprehensive sets of rules.

This distinctive evolution of law in England underscores its reliance on tradition and judicial rulings, setting it apart from other Western European countries that pursued a more systematic approach in their legal codifications.