Complex sentence: World War I delayed the progress of the library; in 1921 it was revived, largely due to the efforts of Mrs. Alfred G. Bookwalter; at the time, the Library Board consisted entirely of women.
Split into simpler sentences: World War I delayed the progress of the library, however progress resumed in 1921. Development resumed largely due to the efforts of Mrs. Alfred G. Bookwalter; at the time, the Library Board consisted entirely of women.