Book: Empires of the Word: A Language History of the World by Nicholas Ostler
Section: The rest of Chapter 6 and beginning of Chapter 7 (Page 260 to 290)
Greek would revive itself after the Roman Empire split and it became the primary language of the most successful Eastern Roman Empire, remaining so up until its fall in the 15th century. Even under the Empire, Greek would have a touch and go status in its own homeland, as constant invasions by Turkic and Germanic people's would threaten its status in the region. Eventually this led to mass emigrations of Greeks, however the Emperors eventually began to move the invaders to other areas of the Empire and resettle Greeks in Greece. Greek would lose out in Anatolia in 1071, with the arrival of the Muslim Seljuk Turks. After the last of the Byzantine states were conquered in 1453, Greek became a minority under the new Ottoman Empire, with Greek's survival then being tied to the Orthodox Church, which had holy texts written primarily in Greek. With the Renaissance, Greek once more became a scholarly language, but never again took the title of lingua franca, which at that time was held by Latin. Greek would no longer be a world player, present only in small communities under its larger benefactors, and despite its resurgence in 1821 as Greece gained independence due to Western intervention, Greek would never again regain its prestige or pride it once had.
When answering the question as to why Greek spread so much, and why the Romans became "hellenophiles", Ostler states that unlike other cultures, Greek was a literate language with a vast collection of cultural icons and writings, which he states developed due to the existence of many different city states in Greece that could all develop in culturally different directions, leading to a large array of works recorded in Greek, which would be impressive to any culture which did not have it. This meant that while Greek did spread, it was usually by outsiders, be it Romans or Macedonians. Despite this, after being conquered by the Turks, their power came to an end.
The history of Europe is dominated by four closely related language families: Celtic, Italic, Germanic, and Slavonic. In every age, their advances across the continent have been warlike, but the languages themselves have fostered different peoples with different values. For the first 250 years, Celtic languages dominate Western Europe and provide relative regional stability, until the onset of the Romans, who introduce Latin. Then after four hundred years of peace, the Germanic tribes at first slowly, but then very quickly, overwhelm the Romans and introduce Germanic. Most of the knowledge of these peoples early on comes from the Greeks. The Greeks remarked that the Celts were tall and fair, and often spoke their harsh language in riddles, and were also considered full of themselves. The Germans were not considered different from the Gauls, as the Greeks only saw cultural, not linguistic differences, due to their lack of desire to learn other languages. They also made no effort to learn about the distinctions between the two peoples. In fact the primary distinction between the two under the Romans was that the Gauls lived on the Roman side of the Rhine, and the Germans on the other. The Germans also did not have agriculture, and were more focused on military prowess than the Gauls. The Romans at first were seen as just another tribe living in Italy, until they started experiencing great success. The Greeks liked to theorize as to why Romans did so well, but never got a distinct answer. Even after the Romans conquered all the Mediterranean coastlines, Greeks never saw Romans as quite on par with themselves. The Slavs were only talked about when they made themselves forcibly known to the Greeks due to raids, and needless to say they were seen as savages related to the Germans but also to the nomadic Sarmatians, remarking on their lifestyle being similar to Germans but many customs coming from the Sarmatians. The author notes that Gaulish spread due to the use of chariots and iron, which the old inhabitants of Europe did not have. The Gauls did not, however, attempt to erase the language or culture of those they conquered, or even to rule them, they simply thrust their neighbors out.