Please, use the library, not games or popular entertainment (documentaries, your avearage YouTube history video, etc).
Please, use the library, not games or popular entertainment (documentaries, your avearage YouTube history video, etc).
One is the genetic heritage, i.e. DNA. If you or your ancestors lived in some place, you may suppose that you might have inherited some of the genes of the ancient people who lived there one thousand years earlier or four thousand years earlier.
It is true that most people who claim to be descendants of some ancient people believe that their relationship with the ancients is such a blood kinship.
You are right that such a belief is mostly false, so many Greeks might share little genetic material with the Ancient Greeks and someone who considers himself/herself, e.g. Polish or Romanian, might happen to have more genetic heritage from some very different people, e.g. from Tatars or Germans.
On the other hand, there is the cultural heritage, i.e. the maternal language and a myriad of customs transmitted from parents to children.
If you consider yourself to belong to some nationality, you might not know that 10 generations earlier your ancestors were considered to belong to another nationality, possibly even to one that you now strongly dislike for some reason.
Nevertheless, some of your ancestors have chosen at some point in time to be integrated into the nationality that you believe now as yours, for various reasons, e.g. marriage, immigration, being a prisoner of war and so on.
From that point of time, all your ancestors transmitted to their descendants the language and customs of your current nationality, which is the result of their willing or unwilling choice.
In my opinion it is correct to claim to be descendant of some people who lived thousands of years ago, when you speak a language derived from their language and you also practice various of their customs, even when (which is likely to be the most frequent case) you share little or no DNA with them.
So it is right for the Modern Greeks to consider themselves descendants of the Ancient Greeks, or for the Romanians, who speak a language derived from Latin, and who, for example, have always cooked and eaten "placinta" with cheese made in the same way as the "placenta" described by Cato the Elder almost 2200 years ago, to consider themselves descendants of the Ancient Romans.
Of course, any such shared cultural heritage with some ancient people should not be used as a basis for claims on a supposed material heritage, like in the case of Israel and other countries where there are territorial claims based on land ownership of supposed relatives from, e.g., 3000 years ago.