See John Selden, Titles of Honor (1672); Antonius Matthaeus, De nobilitate, de principibus, de ducibus, &c., libri quatuor (Amsterdam and Leiden, 1696, lib.
Several details, but only one name, are added in the De Nobilitate et Rusticitate Dialogus (cap. 33) of Felix Hemmerli, a canon of Zurich, who wrote it after 1451 and before 1454; in this last year he was imprisoned by the Schwyzers, whom he had repeatedly insulted and attacked in his books.
Tacitus says of the ancient Germans reges ex nobilitate, duces ex virtute sumunt; i.e.