Complex sentence: Edward Llewellyn was the son of Welsh-born trumpeter James D. Llewellyn (1843--1020), who emigrated to the United States in 1855 and was a featured cornet soloist at the 1893 World's Fair.
Split into simpler sentences: Edward Llewellyn was the son of Welsh-born trumpeter James D. Llewellyn (1843--1020), who emigrated to the United States in 1855. James had been a featured cornet soloist at the 1893 World's Fair.