Colonial history of the United States Lower Louisiana. This vast tract was first settled at Mobile and Biloxi around 1700, and continued to grow when 7,000 French immigrants founded New Orleans in 1718. Settlement proceeded very slowly; New Orleans became an important port as the gateway to the Mississippi River, but there was little other economic development because the city lacked a prosperous hinterland. In 1763, Louisiana was ceded to Spain around New Orleans and west of the Mississippi River. In the 1780s, the western border of the newly independent United States stretched to the Mississippi River. The United States reached an agreement with Spain for
France in the Seven Years' War the Spanish involvement did not provide the relief to the French that had been hoped. Instead French troops were needed to bolster Spanish efforts to invade Portugal, and became bogged down there. Spain also suffered defeats in Cuba and the Philippines in 1762, and by the end of the year both Spain and France were urgently seeking peace. France began asserting control over the Ohio Country as early as 1749, issuing warnings and threats to British colonial traders active in the region. When the French began constructing a series of forts in the Ohio River watershed in 1753, the British