Complex sentence: From 1905 to 1910, when he succeeded Riegl as general curator of the Imperial Central Commission for the study and conservation of art and historical monuments, today Bundesdenkmalamt, he helped save many Austrian art treasures for post-World War I war reparation.
Split into simpler sentences: From 1905 to 1910, he succeeded Riegl as general curator of the Imperial Central Commission for the study and conservation of art and historical monuments, today Bundesdenkmalamt. In this function, he helped save many Austrian art treasures for post-World War I war reparation.