The real city of Sacramento was developed around a wharf, called the Embarcadero, on the confluence of the American River and Sacramento River that Sutter had developed prior to his retirement in 1849 as a result of gold discoveries at Sutter's Mill in Coloma. John Sutter, Sr. had replaced himself with his son, John Sutter, Jr., who noticed growth of trade at the Embarcadero and considered it a viable economic opportunity; the port was used increasingly as a point of debarkation for prospecting Argonauts heading eastwards. Sutter, Jr. had military officials William H. Warner and his assistant, William Tecumseh Sherman, survey his father's holdings for a location where he could establish a new city and create the city over a grid of numbered and lettered streets for organizational purposes. A number of businessmen, including millionaire-to-be Samuel Brannan, future California governor Peter Burnett, and George McDougall, brother of future California governor John McDougall, were attracted to the waterfront location. However, Sutter, Jr. and George McDougall disagreed over the terms of the lease of the location, and a trade war erupted between Sutter's Sacramento City and McDougall's new base of operations at Sutterville. Sutter, Sr., who had opposed many of his son's decisions, resumed control of his business affairs after Sutter, Jr. ended the competition between the two cities; trade in the area was biased toward Sacramento City as a result of Sutter, Jr.'s efforts.