"What Is a Nation?" by French ethnologist Ernest Renan, 1882.

This should be required reading in classrooms across the world even today. While it is certainly a text of its time, it has significant resonances with political questions regarding the nature of political community and of the nation-state.

"A nation is therefore a large-scale solidarity, constituted by the feeling of the sacrifices that one has made in the past and of those that one is prepared to make in the future. It presupposes a past; it is summarized, however, in the present by a tangible fact, namely, consent, the clearly expressed desire to continue a common life. A nation's existence is, if you will pardon the metaphor, a daily plebiscite, just as an individual's existence is a perpetual affirmation of life. That, I know full well, is less metaphysical than divine right and less brutal than so-called historical right. According to the ideas that I am outlining to you, a nation has no more right than a king does to say to a province: 'You belong to me, I am seizing you.' A province, as far as I am concerned, is its inhabitants; if anyone has the right to be consulted in such an affair, it is the inhabitant. A nation never has any real interest in annexing or holding on to a country against its will. The wish of nations is, in all, the sole legitimate criterion, the one to which one must always return."