James K. Polk, a Democrat, vs. Henry Clay, a Whig and perpetual presidential hopeful, battled in the election of 1844 with an added dash of political intrigue — a third-party candidate, James Birney, nominated by the Liberty Party whose central platform focused on the abolition of slavery.

While Polk and Clay, both slaveholders, attempted to dance around the issue of slavery, Polk ultimately appeared more likely to facilitate a compromise between the political factions and geographical differences. Clay, who portrayed his feelings about slavery quite differently in the North than in the South, was eventually identified by the national papers as a “vacillator,” a term that spelled doom for his candidacy.

Polk’s 49.5% popular vote secured the electoral votes that would signal his return to Washington, DC.

While domestic issues are always present, the new president emphasized foreign policy in the campaign, and immediately following his inauguration in March 1845, he set to work on fulfilling those campaign promises.

And the Texas question had to be addressed immediately.

During his last weeks in the White House, John Tyler had strategically sent a joint resolution to Congress authorizing the annexation of Texas. It passed with a simple majority in both houses, just as Tyler’s advisers had predicted; they understood that the Senate would never authorize the annexation by a two-thirds vote, but the use of a resolution avoided the defeat of the idea and allowed Texas to skip the territorial status stage of statehood. In December 1845, Texas became the 15th slave state, and, surprisingly, Mexico had no strong reaction.

At least initially…

When Texas forces moved into the area just north of the Rio Grande, staking a claim to the land between the Nueces River and the Rio Grande, the Mexican government protested the action. When the United States took no action to force the Texans back northward, Mexico City broke off diplomatic relations, and hostilities escalated.

Polk understood the complexity of the situation. Not only was the issue of the southern boundary of Texas an issue, but the president knew that secret negotiations had begun between Great Britain and Mexico about a purchase of California. The thought that Great Britain, already in control of the Canadian territories, might gain a foothold southward from the Oregon Territory to Mexico threatened Polk and the Democrats’ concept of manifest destiny. While the U.S. Army moved into the contested Texas territory, the president sent John Slidell to Mexico City with an offer to purchase California and settle the boundary issue. The Mexican president agreed, but the Mexican military revolted, advocating the return of their “stolen lands.”

Any hope for compromise disappeared when Mexican troops crossed the Rio Grande and killed 11 U.S. soldiers. Polk immediately called a joint session of Congress and asked for a declaration of war, noting that American soldiers had been killed on American soil. The emotional and political response, even by the Whigs who theoretically opposed the war, was overwhelming. With only two senators voting against the declaration, U.S. forces were in the field by May 1846, and seven months later, they had the upper hand. General Zachary Taylor, “Old Rough and Ready,” and his troops, 4,000-plus, were marching toward Monterrey, claiming victory after victory along the way.

Almost simultaneously, General Stephen W. Kearney led a smaller fighting force from Fort Leavenworth to Santa Fe. After gaining control of the “New Mexico” territory, he split his army, sending half toward Chihuahua while the other half, under the command of Captain John C. Fremont, captured northwest Mexico and declared California an independent republic. The “bear flag” revolt was immortalized in the new republic’s flag.

And then things became interesting.

Polk arranged for General Antonia Lopez de Santa Anna to slip safely into Mexico after he promised to gain control of the government and end the conflict for a payoff of only $30 million. Yes, he was the same Santa Anna who had decimated the Texans at the Alamo and continued his raging war against them until he was humiliated at San Jacinto.

As many had warned Polk, once Santa Anna was back in Mexico, he seized power both as commander-in-chief of the Mexican forces and as president — motivated to action against the Texans who had orchestrated his previous downfall. Polk, angered by the betrayal, moved half of Taylor’s forces to General Winfield Scott’s command and ordered “Old Fuss and Feathers” to land at Vera Cruz and march on Mexico City. Scott’s unprecedented amphibious landing at Veracruz gained national headlines, and U.S. citizens waited for the daily news regarding Scott’s dangerous and arduous march westward.

By February 22, 1847, on George Washington’s birthday, the U.S. Army was engaged with Santa Anna’s much larger force at Buena Vista. The future of Texas and the western territories would rest on the outcome of that battle.