It was not uncommon for playwrights in the Golden Age of English theatre, i.e. the late Elizabethan and early Jacobean period, to switch between English and other languages in their dialogue, reflecting the cosmopolitan make-up of London at this time. On occasion playwrights switched into Dutch. There are one or two examples in the work Shakespeare and a few examples in John Marston's 'The Dutch Courtesan' (1605) and, later, Aphra Behn's 'The Dutch Lover' (1673). However, the playwright who used Dutch most frequently was Thomas Dekker (1572-1632). Although his surname seems distinctly Dutch, there is no direct evidence that he had Dutch ancestry. It could be said that Dekker works with stereotypes of the Dutch such as a tendency towards drink, bad language and arguing. It is in the play 'The Shoemaker's Holiday' (1599) performed before Queen Elizabeth in 1600, that Dekker uses Dutch words and phrases to the greatest extent. Here, an English aristocrat disguises himself as a Dutch cobbler to win the heart of a middle-class girl. When he first appears he sings a song, which begins:
Der was een bore van Gelderland,
Frolick si byen,
He was als dronck he cold nyet stand,
Upsolce se byen.
There was a peasant from Gelderland;
Happy they be.
He was so drunk that he could not stand
On his legs.
This language, which is a mixture of Dutch and English words, could variously be described as cod Dutch or something closer to a Dutch pidgin that might have been spoken by Dutch artisans working in London. The fact the Dekker quite often uses Dutch words and phrases in his plays may suggest that there was a significant number of Dutch men and women in the audience who could understand this dialogue.
Further reading: Christopher Joby, The Dutch Language in Britain (1550-1702). Leiden: Brill, 2015, pp. 316-319