John Parker Hale (March 31, 1806 – November 19, 1873) was an American politician and lawyer from New Hampshire. He served in the United States House of Representatives from 1843 to 1845 and in the United States Senate from 1847 to 1853 and again from 1855 to 1865. He began his congressional career as a Democrat, but helped establish the anti-slavery Free Soil Party and eventually joined the Republican Party.
Born in Rochester, New Hampshire, Hale established a legal practice in Dover, New Hampshire after graduating from Bowdoin College. Hale won election to the New Hampshire House of Representatives in 1832 and served as the United States Attorney for New Hampshire under President Andrew Jackson and President Martin Van Buren. He won election to the United States House of Representatives in 1842 but was denied the party's nomination in 1844 due to his opposition to the annexation of Texas. After losing his seat, he continued to campaign against slavery and won election to the Senate in 1846 as an Independent Democrat. In the Senate, he strongly opposed the Mexican–American War and continued to speak against slavery.
Hale helped establish the anti-slavery Free Soil Party and was a candidate for the party's presidential nomination in 1848, but the 1848 Free Soil Convention instead nominated former President Van Buren. He won the party's presidential nomination in 1852, receiving 4.9% of the popular vote in the general election. After the passage of the Kansas–Nebraska Act, Hale joined the nascent Republican Party and returned to the Senate. He served until 1865, at which point he accepted an appointment from President Abraham Lincoln to serve as the Minister to Spain. He held that post until he was recalled in April 1869, at which point he retired from public office.