only encompassed much of the contemporary Dutch-speaking area / Netherlands, but also added classical prestige to the name) and amplified the dichotomy between Early Modern Dutch and the "Dutch" (German) dialects spoken around the Middle and Upper Rhine which had begun to be called overlantsch of hoogdutysch (literally: Overlandish, High-"Dutch") by Dutch merchants sailing upriver. Though "Duytsch" forms part of the compound in both Nederduytsch and Hoogduytsch, this should not be taken to imply that the Dutch saw their language as being especially closely related to the German dialects spoken in Southerwestern Germany. On the contrary, the term "Hoogduytsch" specifically came into being as a special category because Dutch travelers visiting these parts found it hard to understand the local vernacular: in a letter dated to 1487 a Flemish merchant from Bruges instructs his agent to conduct trade transactions in Mainz in French, rather than the local tongue to avoid any misunderstandings. In 1571 use of "Nederduytsch" greatly increased because the Synod of Emden chose the name "Nederduytsch Hervormde Kerk" as the official designation of the Dutch Reformed Church. The synods choice of "Nederduytsch" over the more dominant "Nederlandsch", was inspired by the phonological similarities between "neder-" and "nederig" (the latter meaning "humble") and the fact that it did not contain a worldly element ("land"), whereas "Nederlandsch" did. As the Dutch increasingly referred to their own language as "Nederlandsch" or "Nederduytsch", the term "Duytsch" became more ambiguous. Dutch humanists, started to use "Duytsch" in a sense which would today be called "Germanic", for example in a dialogue recorded in the influential Dutch grammar book "Twe-spraack vande Nederduitsche letterkunst", published in 1584: Beginning in the second half 16th century, the nomenclature gradually became more fixed, with "Nederlandsch" and "Nederduytsch" becoming the preferred terms for Dutch and with "Hooghduytsch" referring to the language today called German. Initially the word "Duytsch" itself remained vague in exact meaning, but after the 1650s a trend emerges in which "Duytsch" is taken as the shorthand for "Hooghduytsch". This process was probably accelerated by the large number of Germans employed as agricultural day laborers and mercenary soldiers in the Dutch Republic and the ever increasing popularity of "Nederlandsch" and "Nederduytsch" over "Duytsch", the use of which had already been in decline for over a century, thereby acquiring its current meaning (German) in Dutch. In the Dutch language itself, Diets(c) (later Duyts) was used as one of several