What branch of linguistics deals with the relationship between languages and hegemony, such as, for example - when Classical Latin became the official language of the Roman Empire, alongside Greek, and also alongside languages of then conquered lands. Is there a branch of linguistics focusing on the connectedness between hegemony and languages?
Perhaps a more alternative accurate term for hegemony would be 'military dominance', or 'cultural dominance', resulting in new words entering daily specialist and general use.
Certainly, the ancient era saw many new concepts, such as theatre in ancient Greece, and politics in ancient Rome.
In more contemporary times, considering Welsh for example, and the impacts made by many years of political struggle, which apparently led to a decline of the language. This example especially made me realise that the potential (longevity, adaption to new concepts) of any language depends on its dominance over other competing languages (i.e. 'languages' meaning integral aspects of [a] society, norms, economy, culture).
I would, finally, like to make one observation. It seems to me, if any one nation were to succeed in establishing a permanent hegemony (social, cultural, political means), then it may be inevitable that eventually all nations would adopt the dominant language, and ultimately its social and cultural ideals. Is this the ultimate destiny of the majority of contemporary languages - to become dominant or extinct, resulting in only one common language. In Wales, the view is: a strong economy is necessary for a thriving Welsh (identity and language) society and culture. In fact, history shows a language becomes dominant through the processes of hegemony, where languages succeed and become dominant through popular acceptance and adoption - e.g. Welsh is sometimes considered a harder language to learn and use compared to English, which is arguably one cause for its decline. On the other hand, many people define their whole identity according to the historical significance of Welsh, which in turn becomes the counter-force against the more popular (globally understood) English language, though great effort is made to ensure Welsh equivalent to new English words are actually Welsh, rather than anglicised Welsh. However, the Internet is an English invention adopted by every nation, including its new words and phrases.