Complex sentence: At the start of World War I, Joseph moved to New York City and reopened the gallery there at 43 East Fifty-Seventh Street, where it stayed in business until 1949, two years after Joseph's death.
Split into simpler sentences: At the start of World War I, Joseph moved to New York City and reopened the gallery there at 43 East Fifty-Seventh Street. It stayed in business until 1949, two years after Joseph's death.