Complex sentence: Jazzhus Montmartre was opened in 1959 bei Anders Dyrup with a two week stint by George Lewis and in the beginning the program was dominated by Dixieland-Jazz (then very popular in Denmark).
Split into simpler sentences: Jazzhus Montmartre was opened in 1959 by Anders Dyrup with a two week stint by George Lewis. In the beginning the program was dominated by Dixieland-Jazz (then very popular in Denmark).