Zachary Taylor (1784 to 1850) was an American military officer who served as the twelfth president of the United States. Born to a family of prominent Virginian planters, Taylor joined the US Army in 1808 and eventually rose to the rank of major general. Nicknamed 'Old Rough and Ready' by his men, he played a significant role in the Mexican-American War (1846 to 1848), leading US forces to victory in such actions as the Battle of Monterrey (21 to 24 Sept 1846) and Battle of Buena Vista (22 to 23 Feb 1847). He used his newfound status as a war hero to win election to the presidency in 1848. However, he abruptly died a little over a year into his term, on 9 July 1850.

Zachary Taylor was born on 24 November 1784 on his family's plantation in Orange County, Virginia. He was the third of nine children born to Richard Taylor, a prominent planter and veteran of the American Revolution, and his wife, Sarah Dabney Strother Taylor. His family was an old one, with deep roots in the Commonwealth of Virginia; he was related to the distinguished Lee family of Virginia and was a distant cousin of both President James Madison (1751 to 1836) and Confederate General Robert E. Lee (1807 to 1870). But by the time of Zachary's birth, the soil on the family's tobacco plantation was almost depleted of nutrients, forcing Richard Taylor to search for more fertile lands out west. The Taylors settled in the burgeoning frontier community of Louisville, Kentucky, where they initially lived in a small cabin. Before long, they were prosperous enough to upgrade to a brick home, and by the turn of the century, Richard Taylor had accumulated 10,000 acres of land throughout Kentucky as well as 26 slaves.

Growing up, Zachary Taylor received some formal education, but he was mostly educated at home by his mother. The Kentucky of his childhood was a dangerous place, the scene of bloody fighting between Anglo-American settlers and various Native American peoples that was part of the Northwest Indian War (1785 to 1795). Taylor would have been acutely aware of this bloodshed and indeed, this frontier violence may have influenced him to pursue a military career. He joined the Kentucky militia in 1806 and, two years later, was commissioned in the US Army as a first lieutenant. His first assignment was to a military camp near New Orleans in 1809, which was disease-ridden and woefully undersupplied. Taylor soon fell sick and returned home to Louisville to recover. While there, he met Margaret Mackall Smith, the daughter of a wealthy Maryland planter. They were married in June 1810 and soon moved into a small cottage in Baton Rouge, Louisiana.

After the outbreak of the War of 1812 (1812 to 1815) between the United States and the United Kingdom, many Northwestern Native American nations decided to ally themselves with the British, seeing the war as their best chance to resist US encroachment onto their remaining lands. Taylor, now a captain, was ordered to take command of Fort Harrison in the Indiana Territory, which was vulnerable to Native attack. On 4 September 1812, Fort Harrison came under siege by a 600-man force consisting of Miami, Potawatomi, Winnebago, and Kickapoo Indians. Despite being hopelessly outnumbered, Taylor refused an offer to surrender – that night, one warrior set fire to the fort's blockhouse as a distraction while the rest assaulted the west wall. Taylor organized a bucket brigade to put out the fire, putting his surgeons and the wives of his soldiers to work, while the garrison held back the attackers.

Though the fire was eventually put out and the Native Americans repulsed, the next morning found that most of the garrison's food supply had been destroyed in the fire; all the besiegers had to do now was starve them out. Luckily for Taylor, a detachment of 1,000 reinforcements arrived on 12 September, lifting the siege and forcing the Indian attackers to melt back into the woods. Taylor had held the fort at a time when the US sorely needed victories – he was rewarded with a brevet promotion to major. He would spend the rest of the war fighting Indians on the frontier, at places such as Wild Cat Creek (Nov 1812) and Credit Island (Sept 1814).

After the war, Taylor spent two years stationed in the Michigan Territory before returning to Louisville with his growing family – by 1826, he and Margaret had had six children, four of whom would survive to adulthood (including Richard Taylor, future Confederate general). In April 1819, he was promoted to lieutenant colonel and, the following year, was given command of an infantry regiment in Louisiana. In 1822, he was sent to Baton Rouge on recruitment duty; while there, he continued to improve his Baton Rouge home and began to buy properties along the Mississippi River, which proved to be lucrative investments. In 1832, he led troops during the Black Hawk War (April to Aug 1832), one of the last major Indian Wars in the Northwest region. During this campaign, his 17-year-old daughter, Sarah Knox 'Knoxie' Taylor, fell in love with Lt. Jefferson Davis (1808 to 1889), a young officer under Taylor's command and the future president of the Confederate States. Though Taylor initially disapproved of the match, he eventually gave his reluctant approval, and the couple married in June 1835. However, Sarah would tragically contract malaria and die only three months after her marriage.

In 1837, Taylor was sent to Florida to help fight the Second Seminole War (1835 to 1842). Waged against various southeastern Native American tribes collectively referred to as 'Seminoles', the war was a long and grueling conflict, one that utilized guerrilla warfare in the swampy Floridian terrain. Taylor respected the guerrilla tactics of his Native American adversaries, even as he sought to defeat them and deprive them of their lands. On 25 December 1837, Taylor and 1,100 US soldiers attacked a large Seminole encampment at the Battle of Lake Okeechobee. Though the Seminoles were greatly outnumbered – there were only 400 warriors present – they held off Taylor's troops long enough to evacuate their camp. Despite this defeat, Taylor was promoted to brigadier general and given command of all US troops in Florida; it was during this period that he earned his famous nickname 'Old Rough and Ready'. In 1840, he left the Floridian frontier and purchased the 1,923-acre (778 ha) Cypress Grove Plantation in Mississippi. On this plantation, which was toiled over by 127 slaves, Taylor grew cotton, tobacco, and other cash crops, but often failed to turn a profit due to chronic flooding and frequent pest infestations

In 1843, the United States entered negotiations to annex the newly independent Republic of Texas. There was, however, a significant obstacle to this, as Mexico had never recognized Texas' independence. Nor did Mexico accept the claim that the Rio Grande marked Texas' southern border, since historically, the boundary of Mexican Texas had been the Nueces River, 150 miles (240 km) north of the line Texas now claimed. In the US, the Democratic Party – the political party most closely associated with the concept of 'Manifest Destiny' and US expansionism – clamored for the annexation of Texas at all costs. In 1844, the Democratic candidate James K. Polk (1795 to 1849) won election to the presidency and, the following year, ordered Taylor to take command of the 4,000-man Army of Occupation and assert the United States' claim to both Texas and the Rio Grande border. Though Taylor was hardly the most senior general in the army, he got the job because Polk was a jealous man who did not see the apolitical Taylor as threatening; most of the other army officers, like Major General Winfield Scott (1786 to 1866), were members of the rival Whig Party who nursed political ambitions and were therefore distrusted by Polk.

In June 1845, Taylor marched his army to Corpus Christi at the mouth of the Nueces River in Texas, where he spent the next several months training his troops as he awaited further developments. When talks between US and Mexican negotiators quickly broke down – as Polk had anticipated they would – Taylor was ordered to take his army into the disputed territory, and to get as close to the Rio Grande as he dared. He arrived in March 1846, constructing Fort Texas and aiming his guns at the town of Matamoros across the river, where a strong Mexican force was gathering. When the Mexicans demanded that Taylor withdraw, 'Old Rough and Ready' responded by blockading the mouth of the Rio Grande, preventing any supplies from reaching the Mexican army by water. On 23 April, the Mexican president issued a proclamation blaming the US for the hostilities and ordering the commander of Matamoros, General Mariano Arista, to undertake defensive operations. Arista obeyed, sending 1,600 cavalrymen across the river. On the morning of 25 April, the Mexican cavalry clashed with 60 US dragoons under Captain Seth Thornton, killing or capturing all but one.

After this brief fight, known as the Thornton Affair, Arista knew the clock was ticking for him to strike a decisive blow against Taylor's force. He planned to cross the river and encircle the smaller American army, but his crossing was delayed by a lack of boats. By the time the Mexican army had crossed the river, Taylor had withdrawn, leaving only a small garrison behind to man Fort Texas. Arista decided to lay siege to the fort with his 3,270 men, only for Taylor to return with 2,288 soldiers. The ensuing Battle of Palo Alto (8 May) began with an artillery duel, with Taylor's cannons inflicting more damage than they received. Arista ordered his cavalry to charge, but his riders could not break the 'hollow square' formation assumed by the American infantrymen. As night fell, neither army had landed a decisive blow, but Arista decided to retreat, hoping to find better ground from which he could force Taylor to attack him. Taylor struck before Arista was ready, however, assaulting the Mexican flank at the Battle of Resaca la Palma (9 May). Arista was defeated and forced back across the Rio Grande. The victory turned Taylor into a war hero back in the US and earned him a promotion to major general.

Taylor pursued the beaten Mexican force across the Rio Grande and occupied first Matamoros and then the town of Camargo. His army rested here for the next six weeks as it awaited supplies and reinforcements; during this time, his army was ravaged by dysentery, which killed one in eight of his soldiers. In September, Taylor advanced with 6,000 men to the strategic city of Monterrey, which was defended by 7,000 Mexican soldiers and 3,000 irregular fighters. On 21 September, Taylor opened the Battle of Monterrey by demonstrating against the eastern part of the city with his main body while 2,000 troops under General William Worth attacked from the west. By the 23rd, both parts of Taylor's army had forced their way into the city, leading to brutal house-to-house fighting.

Aware that both armies were exhausted from the fighting, Taylor offered an armistice on 24 September. Since his army was undersupplied and could not afford to take prisoners, he promised to let the Mexican soldiers retreat unmolested in return for the city's surrender. This was accepted, and Taylor gained control of Monterrey. While the battle only enhanced his reputation with the American public, it earned him the wrath of Polk. The president was incensed that Taylor had agreed to an armistice, believing that he had wasted a chance to destroy the Mexican army. Polk, who was also growing threatened by Taylor's increasing popularity, opted to strip his army of its veteran soldiers and send them to General Scott, who was preparing to invade the Mexican heartland. Taylor and his weakened army were left at Monterrey, a fact that the Mexicans learned from an intercepted letter. Hoping to destroy Taylor's force before Scott's new army arrived, Mexican General Antonio López de Santa Anna (1794 to 1876) raised an army of 20,000 men and hurriedly marched north.

Taylor, learning of Santa Anna's approach, did not retreat but established a strong defensive line near the town of Saltillo. On 22 February 1847, Santa Anna lined his large army up across from the Americans in a show of intimidation before sending over an officer to demand their surrender; Taylor simply responded, "Tell Santa Anna to go to hell!" The next day marked the fierce Battle of Buena Vista, the largest engagement of the war. Santa Anna launched wave after wave of assaults on the American position, almost breaking their line. During a critical point in the fighting, an officer told Taylor that they were beaten, to which the general coolly replied, "That is for me to determine". When the Mexicans breached the American line, Taylor deftly plugged the gap by sending in the Mississippi volunteers, led by his former son-in-law, Jefferson Davis. By nightfall, the Americans controlled the battlefield, and the next morning, Santa Anna withdrew. The battle had cost 700 American and over 1,500 Mexican casualties.

After his victory at Buena Vista, Taylor pulled back to Monterrey, where he remained with his weakened command until November 1847, when he returned to the United States. Despite Polk's attempts to sideline him, he arrived in New Orleans to a hero's welcome, and, indeed, political clubs supporting a Taylor presidential candidacy had begun to sprout up across the country. Taylor was far from the typical presidential candidate. Until this point, he had remained largely apolitical, refusing to speak his mind on current issues. His military career had given him a healthy skepticism of politicians, and, in fact, he had never even voted before. But his lack of political baggage proved beneficial. Northern Whigs saw him as a popular war hero who had the best chance of toppling Polk's ilk of expansionist Democrats. Southerners knew that he was a plantation owner with hundreds of slaves and believed that he would defend their 'peculiar institution'. In September 1847, Taylor released a letter publicizing some of his views, including low tariffs.

In February 1848, the Treaty of Guadalupe Hidalgo ended the war with Mexico, forcing the Mexican government to cede 529,000 square miles of land to the US; comprising modern California, New Mexico, and Utah, this territory was known as the Mexican Cession. Satisfied that he had kept his imperialist promises, Polk announced that he would not seek a second term; the Democrats instead chose Senator Lewis Cass of Michigan as their nominee. While Taylor had initially stated that he would not accept the nomination from either party, he eventually yielded to popular pressure and sought the nomination of the Whig Party. In June 1848, he attended the Whig National Convention in Philadelphia, in which his rivals included General Winfield Scott and Henry Clay (1777 to 1852). Taylor won the nomination on the fourth ballot, and the convention chose Millard Fillmore (1800 to 1874) as his vice-presidential candidate. In the general election, Taylor ignored the Whig Party's platform and instead ran merely on his own military record and personal popularity. This proved successful – in November, Taylor defeated both Cass and the third-party candidate Martin Van Buren (1782 to 1862), winning 163 of the 290 electoral votes and 47.3% of the popular vote.

As soon as he was sworn into office on 4 March 1849, Taylor felt the full weight of the nation on his shoulders. The Mexican Cession had reopened old sectional wounds between the North and the South, particularly regarding slavery – should the 'peculiar institution' be allowed to expand into the newly conquered territories? Many Northern politicians argued against it. Aside from the moral argument put forth by the abolitionist minority, Northerners feared that adding more 'slave states' to the Union would unfairly increase the political power of the South, already disproportionate in Congress. Additionally, the former Mexican authorities had already abolished slavery throughout most of these territories, and the people who lived there now were largely against the institution. Southern politicians vehemently opposed any restrictions on slavery. They argued that the Missouri Compromise of 1820 had allowed for slavery to exist in any territory below the 36° 30' parallel.

Though Taylor was a slaveholder himself, he did not see the expansion of slavery into these lands as practical; after all, little of the territory in the Mexican Cession was usable for cotton cultivation. In 1849, he advised the territories of California and New Mexico to draft their own state constitutions and decide for themselves whether they wanted to permit slavery. This sparked fierce backlash from Southern politicians, since both of these territories would likely choose to enter the Union as 'free states'. As debate raged in Congress, several Southern leaders met with Taylor to urge him to change his mind, threatening secession if slavery was banned in California. Enraged by these threats, Taylor promised that if they did secede, he would march south with an army and hang any secessionists he could find "with less reluctance than he had hanged spies and deserters in Mexico" (quoted in American Battlefield Trust).

As tensions worsened, Henry Clay and several other politicians worked to resolve the crisis, creating several proposals that would form the basis of the Compromise of 1850. Taylor impatiently urged them to finish the compromise, although he would not live to see its passage. On 4 July 1850, during Fourth of July celebrations, he consumed large amounts of cherries and iced milk to cool off. He then fell ill, and although his condition was intitially mild, it soon worsened. He died on 9 July 1850 at the age of 65, likely of gastroenteritis. He was succeeded by his vice president, Fillmore, who finished the rest of his term.