Complex sentence: The most conclusive evidence is that from 1902 to the summer of 1904 Etta Place was most definitely in South America, whereas in 1903, Ann Bassett was arrested and for a time incarcerated in Utah.
Split into simpler sentences: The most conclusive evidence is that from 1902 to the summer of 1904 Etta Place was most definitely in South America. In 1903, Ann Bassett was arrested and for a time incarcerated in Utah.