Hi, Bob - how right you are! I just looked up "deutsch" in our standard etymologic dictionary. Old thiudisc- is a derivation of Indogermanic teutâ and this means: folk, people.
So all the continental-european German tribes called themselves Deutsch or Dutch, Diets, Dütsch and so on while using their language as opposite to Latin as the language of church and government. In latin texts of Charlemagne's times it appears as theodiscus, but note that the German word is older and given as a name by the people to themselves.
Deutschland (Germany) is a composition of the adjective deutsch and the noun land and appeared first in the 14th century, but not so often; we mostly find deutsches land or in the folksongs of the 16th and 17th century.

Wilfried