2019 July 25 – White Sands National Park, formally a National Monument established in 1933 by President Hoover, is created by signature of U.S. President Donald Trump after signing the National Defense Authorization Act for Fiscal Year 2020.
2000 July 25 – Valles Caldera National Preserve was established by signature of U.S. President Bill Clinton.
1991 July 2 – The Pecos National Monument is re-established as Pecos National Historical Park by the National Park Service.
1968 July 1 – U.S. President Lyndon B. Johnson signs An Act to establish a national trails system, and for other purposes, creating the National Trails System. [put the link to the national trails in New Mexico].
1947 July 8 – Rancher Mac Brazel discovers wreckage of a Unidentified Flying Object outside of Roswell, New Mexico.
1945 July 16 – The World’s First Atomic bomb is detonated at the Trinity Site near Alamogordo as part of the Manhattan Project.
1928 July 2 – U.S. President Calvin Coolidge issues an executive order enlarging Aztec Ruin National Monument and changing the name to Aztec Ruins National Monument.
1908 July 2 – U.S. President Theodore Roosevelt established Alamo National Forest and Pecos National Forest by executive order.
1905 July 21 – U.S. President Theodore Roosevelt established the Gila Forest Reserve through proclamation.
1902 July 26 – U.S. President Theodore Roosevelt issues a proclamation creating the Lincoln Forest Reserve.
1881 July 14 – New Mexico outlaw Billy the Kid, famous for the Lincoln County War, is killed by Doña Ana County Sheriff Pat Garret. Billy the Kid is hastily buried in Fort Sumner, New Mexico.
1875 July 30 – U.S. President Ulysses S. Grant appoints Samuel Beach Axtell the ninth Governor of the Territory of New Mexico.
1871 July 27 – U.S. President Ulysses S. Grant appoints Marsh Giddings the eighth Governor of the Territory of New Mexico.
1861 July 25 – Texas cavalry under the command of Lieutenant Colonel John R. Baylor invades the Territory of New Mexico and occupies the town of Mesilla.
1852 July 15 – U.S. President Millard Fillmore appoints William Carr Lane the second Governor of the Territory of New Mexico.
1849 July 6 – Joint Boundary Commission organized to formally establish New Mexico’s Southern border with Mexico, which would not be finalized until the Treaty of Mesilla aka the Gadsden Purchase in 1854, which established the current boundaries.
1848 July 4 – Date when the Treaty of Guadalupe Hidalgo is made public in Washington, which resulted in the acquisition of New Mexico and California and recognition of the Rio Grande as Texas’ Southern border with Mexico.
1835 July – The Mexican Government appoints Albino Pérez as Gobernador de Santa Fe de Nuevo México.
1822 July 5 – Francisco Xavier Chávez assumes office as the second Géfe político de Santa Fe de Nuevo México.
1807 July 1 – US Army Captain Zebulon Pike is expelled from Nueva España after being arrested by Spanish cavalrymen in the San Luis Valley while he was on a reconnaissance mission.
1697 July 2 – The Spanish Crown appoints Don Pedro Rodriguez Cubero to become Gobernador de Nuevo Méjico.
1659 July 11 – The Spanish Crown appoints Capitán Don Bernardo López de Mendizábal to become Gobernador de Nuevo Méjico.
1598 July 12 – Spaniard Don Juan de Oñate y Salazar establishes the Virreinato de Nueva España colony of Santa Fe de Nuevo Méjico at the village of San Juan de los Caballeros adjacent to the Ohkay Owingeh Pueblo at the confluence of the Rio Grande and the Río Chama. The colony will eventually encompass most of the future U.S. states of New Mexico and Colorado and portions of Kansas, Oklahoma, Texas, Arizona, and Utah.
1540 July 7 – Conquistador Francisco Vásquez de Coronado reaches the Zuni pueblo of Hawikuh. The Zuni resist but are driven off by the Spanish soldiers.