Johannes Hadlaub is one of the Minnesingers whose works are recorded in Codex Manesse

Codex Manesse

The Codex Manesse, Manesse Codex, or Große Heidelberger Liederhandschrift is a Liederhandschrift , the single most comprehensive source of Middle High German Minnesang poetry, written and illustrated between ca. 1304 when the main part was completed, and ca...

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He was a citizen of Zürich

Zürich

Zurich is the largest city in Switzerland and the capital of the canton of Zurich. It is located in central Switzerland at the northwestern tip of Lake Zurich...

, and is on record as buying a house there in 1302.

There are 51 songs by Hadlaub in the Codex Manesse, and it is commonly assumed that Hadlaub was actively involved in its compilation.
This assumption was fictionalised in a poetic novella, "Hadlaub" (in the Züricher Novellen, 1878), by Gottfried Keller

Gottfried Keller

Gottfried Keller , a Swiss writer of German-language literature, was best known for his novel Green Henry .- Life and work :...

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