Complex sentence: Leidesdorff died suddenly three years later, on May 18,1848, at the age of 38, unmarried and with no other family in California, "intestate" but leaving a large estate of property at the dawn of the California Gold Rush.
Split into simpler sentences: Leidesdorff died suddenly three years later, on May 18,1848, at the age of 38. He died "intestate", leaving a large estate of property at the dawn of the California Gold Rush.