Complex sentence: In 1888, Illingworth founded and became the major share holder in the Centennial Land Bank, a company formed to finance speculation on real estate during the Victorian land boom, an economic bubble that had begun in the early 1880s.
Split into simpler sentences: In 1888, Illingworth founded and became the major share holder in the Centennial Land Bank. This was a land bank formed to finance speculation on real estate during the Victorian land boom, an economic bubble that had begun in the early 1880s.