Complex sentence: It was the reputation of Henri Matisse that drew most of them, but Matisse made relatively little impact on von Dardel; instead he was influenced by the Post-Impressionists, the pure colours of the Fauvists, and Japanese woodcuts.
Split into simpler sentences: It was the reputation of Henri Matisse that drew the others, but Matisse made relatively little impact on von Dardel. Instead he was influenced by works of the Post-Impressionists, the pure colours of the Fauvists, and Japanese woodcuts.