The constitutional rules that govern how states engage with international law have profound implications for foreign affairs, yet we lack comprehensive data on the choices countries make and their motivations. We draw on an original dataset that covers 108 countries over a nearly two-hundred-year period to map countries’ foreign relations law choices and trace their evolution. We find that legal origins and colonial legacies continue to account for most foreign relations law choices. A small number of models emerged in the nineteenth and early twentieth century in Western Europe, subsequently spread through colonial channels, and usually survived decolonization. Departures from received models are rare and usually associated with major political shifts. Prominent political science accounts that emphasize how states design their foreign relations law strategically to enhance their international credibility or entrench democracy or human rights appear to have limited explanatory power over the bulk of foreign relations law today.

中文翻译：

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对外关系法的全球演变

规范国家如何参与国际法的宪法规则对外交事务具有深远的影响，但我们缺乏关于国家做出的选择及其动机的全面数据。我们利用涵盖近 200 年期间 108 个国家的原始数据集来绘制各国的外交关系法律选择并追踪其演变。我们发现，法律渊源和殖民遗产仍然是大多数外交关系法选择的原因。少数模式于 19 世纪和 20 世纪初在西欧出现，随后通过殖民渠道传播，通常在非殖民化中幸存下来。与已接收模型的偏离很少见，通常与重大政治转变有关。