Number of Americans who died in the Mexican-American War: 13,000²
Number of Mexicans who died in the Mexican-American War: perhaps 25,000
Number of Mexican civilians who died: 1,000³

Number of American who volunteered for service in the Mexican-American War: over 60,000
Percentage that were foreign-born: about 40%⁴

Annual cumulative mortality rate for American soldiers in the Mexican-American War: 153.5 per thousand troops
Annual cumulative mortality rate for Union forces during the Civil War: 98 per thousand troops

American population of California in 1846: 500
Mexican population of California in 1846: 8,000 to 12,000⁵⁶

Area of territory gained by the United States between 1846 and 1848: more than 1 million square miles

Price paid for land acquired through the Mexican-American War: $15 million
Price paid for the Louisiana Purchase: $15 million

Stars on the American flag from July 4th, 1846 to July 3rd, 1847: 28 stars (Texas)
Stars on the American flag from July 4th, 1847 to July 3rd, 1848: 29 stars (Iowa)
Stars on the American flag from July 4th, 1848 to July 3rd, 1851: 30 stars (Wisconsin)
Stars on the American flag from July 4th, 1851 to July 3rd, 1858: 31 stars (California)⁷