The five Oppenheimer brothers came to California and opened up several of their own stores to trade goods with gold miners, much like most Jewish immigrants to North America at that time. Soon one of the brothers Charles Oppenheimer heard about the gold rush in British Columbia and went to investigate, in a year the rest of the brothers joined him and opened up a trading firm in Victoria and soon in Barkerville as well. When the gold rush was dying down David saw the possibility of Burrard Inlet becoming a great port in the future, but only if the railway ended in Vancouver. Even though Vancouver was likely to win the race he decided to make sure of that, so bought a lot of land on south shore of the inlet and when General Manager of CPR William Van Horne came Oppenheimer took him for a row and showed him all that great land he acquired before hand and offered half of it along with some land of other major landholders.
With that move he made sure Vancouver will win. Later on when CPR was built, he was elected as mayor and donated a lot of the land which he owned to schools and parks. David Oppenheimer built an electric car system, an electric company, and a pipe to supply the city with water. If it wasn't for David, and his ambition for creating a new city Vancouver would be like most of BC is right now.