Imagine you’re in Canada and you buy a handmade leather jacket from a small shop in Italy. The payment is processed through a bank in Ireland, and the jacket is shipped from a warehouse in Germany. It arrives damaged. You decide to sue. But whose law applies? Canada’s? Italy’s? Germany’s?

This maddening puzzle is the daily work of “private international law,” and for centuries, the answer was a chaotic mess. That is, until a 19th-century German legal scholar named Friedrich Carl von Savigny came along and gave the world a revolutionary new way to think—a kind of GPS for finding the law. He didn’t just propose a new rule; he changed the entire way we approach cross-border legal problems.

The Old Way: A Labyrinth of Rules

Before Savigny, courts were tied up in knots by a system we now call the “statute theory.” Judges would try to classify laws into arbitrary categories: were they “real” (applying to things, like land), “personal” (following a person wherever they went), or “mixed”? This approach was confusing, rigid, and often led to courts simply favoring their own local laws. It was a system that looked inward, at the nature of the law itself, rather than outward, at the nature of the dispute.

Savigny’s Breakthrough: Every Problem Has a Home

Savigny, a leading figure of the German Historical School of Law, turned this entire way of thinking on its head. He argued that instead of analyzing the law, we should analyze the legal relationship itself. In his masterwork, System of Modern Roman Law, he introduced his famous “seat of the legal relationship” theory (in German, Sitz).

His idea was beautifully simple: every legal relationship—every contract, every property dispute, every marriage—has a natural “seat” or a center of gravity. To find the right law, you just had to find the relationship’s home. He broke it down logically:

  • For a person’s status (like marriage or legal capacity), the natural seat is their domicile. The law of their home should govern them.
  • For property, the seat is obviously where the property is physically located.
  • For a contract, the seat is often where the contract is meant to be performed, or whatever place the parties themselves intended.

This was a landmark change. It shifted the focus from the subjective and political nature of laws to the objective facts of the case. For the first time, there was a clear, logical method: look at the relationship, find its seat, and apply that location’s law.

A Global Vision for Justice

Savigny’s theory was powered by an even bigger, more radical idea for his time: universalism. He believed that the community of nations formed a single legal community, where all laws were, in principle, equal. He argued that a case should be decided the same way whether it was heard in Berlin or Rome, which required courts to apply foreign law not as a matter of political politeness or “international comity,” but because justice demanded it. While this vision of a world without legal chauvinism remains idealistic, it provided a powerful theoretical basis for the internationalization of law that we see today, especially in an era of globalization.

Savigny’s Legacy and the Puzzles That Remain

Savigny’s influence is immense; his thought laid the foundation for modern private international law. His DNA is clearly visible in later, more flexible theories like the “most significant relationship” principle used in many countries today, which asks judges to weigh various factors to find the law with the deepest connection to the dispute.

But his theory wasn’t perfect. He created a logical framework, but what happens when different legal systems can’t even agree on what the problem is? For instance, if one country sees a broken promise to marry as a breach of contract and another sees it as a tort (a civil wrong), they will look for the “seat” in completely different places. This “characterization problem,” as lawyers call it, reveals the logical loop in the system: to apply the rule, you first have to categorize the problem, and you almost always do that using your own local law’s mindset.

Even so, Savigny’s achievement remains monumental. He was a transitional figure who took law from a feudal, rule-obsessed framework into the modern era. He taught us to ask the right question—not “What does my law say?” but “Where in the world does this problem truly belong?” And in our deeply interconnected world, that question is more relevant than ever.