Here's a song that seems to date back before Dutch and German separated. It is in "plat-Deutch" (low German). The theme is surprisingly modern. My English translation appears before each verse in the d(e)utch

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Dat du myn Schatsken bist

I hold you in my heart, whisper you care
Come in the night, come in the night, say who you are

Dat du myn Schatsken bist, dat du well weest,
Kum by de nacht, kom by de nacht, segg wo du heest
Kum by de nacht, kom by de nacht, segg wo du heest

Come in the darkest night, come at 1am
Mother's asleep, father's asleep, I lie alone

Kum du um mitternacht, kum du klok een
Vader slopt, Moder slopt, ik slaap aleen

Tap on the window love, open the door
Father thinks, mother thinks, it is the wind

Klop an de kamerdor, faat an de klink
Vader meent Moder meent, dat deit de Wind