Most of that land was too dry and too mountainous to support a large population. About 80,000 Mexicans inhabited California, New Mexico, Arizona, and Texas during the period 1845 to 1850, with far fewer in Nevada, southern and western Colorado, and Utah. On 1 March 1845, U.S. President John Tyler signed legislation to authorize the United States to annex the Republic of Texas, effective on 29 December 1845. The Mexican government, which had never recognized the Republic of Texas as an independent country, had warned that annexation would be viewed as an act of war. Both the United Kingdom and France recognized the Republic of Texas's independence and repeatedly tried to dissuade Mexico from declaring war against its northern neighbor. British efforts to mediate the quandary proved fruitless, in part because other political disputes (particularly the Oregon boundary dispute) arose between Great Britain (as the claimant of modern Canada) and the United States.
Most of that land was too dry and too mountainous to support a large population About 80000 Mexicans inhabited California New Mexico Arizona and Texas during the period 1845 to 1850 with far fewer in Nevada southern and western Colorado and Utah On 1 March 1845 US President John Tyler signed legislation to authorize the United States to annex the Republic of Texas effective on 29 December 1845 The Mexican government which had never recognized the Republic of Texas as an independent country had warned that annexation would be viewed as an act of war Both the United Kingdom and France recognized the Republic of Texas's independence and repeatedly tried to dissuade Mexico from declaring war against its northern neighbor British efforts to mediate the quandary proved fruitless in part because other political disputes (particularly the Oregon boundary dispute) arose between Great Britain (as the claimant of modern Canada) and the United States