Short answers, pulled from the story.
Abel Seyler, a Hamburg merchant and banker originally from Switzerland, established the Seyler Theatre Company in 1769. He became the main owner after continuing the work of the Hamburgische Entreprise troupe.
The company performed at the Weimar Schlosstheater for three years following an invitation from Duchess Anna Amalia of Brunswick-Wolfenbüttel. This engagement solidified their reputation as the best theatre company in Germany during that period.
Friedrich Maximilian Klinger wrote the play Sturm und Drang originally for the Seyler Theatre Company. The production premiered in 1777 after years of development and defined the entire literary movement across Germany.
Between 1777 and 1778, the company employed some 230 actors, singers, and musicians. This ensemble included an orchestra, a ballet, house dramatists, and set designers who worked together to produce dramatic works.
Seyler's brother-in-law Johann Gerhard Reinhard Andreae intervened to save the troupe when financial collapse threatened operations in 1770. His support prevented total dissolution and allowed the enterprise to continue performing through difficult years.