Although Tacitus began his writing career during the Principate at the end of the first century CE, the dominant approach to thinking about political life was still guided by Republicanism, a constellation of concepts from the mid-first century BCE Roman Republic. Republicanism held that there was only one type of monarchy and that it necessarily precluded libertas. Tacitus, who was living under different iterations of monopolistic power in the Principate, questions this tenet by examining various Germanic tribes. The Germania explores different types of monarchical arrangements, showing that monarchy is not a one-size-fits-all form and that there are significant political differences among the Germanic monarchies, some of which preserve libertas. In this examination, he highlights the inapplicability of Republicanism to a system as dynamic as the Principate.

尽管塔西佗在公元一世纪末的元首统治时期开始了他的写作生涯，但思考政治生活的主导方法仍然受到共和主义的指导，这是来自公元前一世纪中叶罗马共和国的一系列概念。共和主义认为只有一种君主制，它必然排除自由。塔西佗生活在元首国不同时期的垄断权力之下，他通过考察不同的日耳曼部落来质疑这一原则。日耳曼尼亚探讨了不同类型的君主制安排，表明君主制不是一种一刀切的形式，日耳曼君主制之间存在显着的政治差异，其中一些保留了自由。在这次审查中，他强调了共和主义不适用于像元首制这样充满活力的制度。