Speech-Differentiation in the Case of Race-Mixture,"[9] Professor Hempl
has discussed the conditions under which language-rivalry takes place, and
states the results that follow. His conclusions have an interesting
bearing on the question which we are discussing here, how and why it was
that Latin supplanted the other languages with which it was brought into
contact.

He observes that when two languages are brought into conflict, there is
rarely a compromise or fusion, but one of the two is driven out of the
field altogether by the other. On analyzing the circumstances in which
such a struggle for supremacy between languages springs up, he finds four
characteristic cases. Sometimes the armies of one nation, though
comparatively small in numbers, conquer another country. They seize the
government of the conquered land; their ruler becomes its king, and they
become the aristocracy. They constitute a minority, however; they identify
their interests with those of the conquered people, and the language of
the subject people becomes the language of all classes. The second case
arises when a country is conquered by a foreign people who pour into it
with their wives and children through a long period and settle permanently
there. The speech of the natives in these circumstances disappears. In the
third case a more powerful people conquers a country, establishes a
dependent government in it, sends out merchants, colonists, and officials,
and establishes new towns. If such a province is held long enough, the
language of the conqueror prevails. In the fourth and last case peaceful
bands of immigrants enter a country to follow the humbler callings. They
are scattered among the natives, and succeed in proportion as they learn
the language of their adopted country. For their children and
grandchildren this language becomes their mother tongue, and the speech of
the invaded nation holds its ground.