18 October - United States takes possession of Alaska in 1867

The Alaska Purchase was the United States' acquisition of Alaska from the Russian Empire. Alaska was formally transferred to the United States on October 18, 1867, through a treaty ratified by the United States Senate and signed by President Andrew Johnson.

Russia had established a presence in North America during the first half of the eighteenth century, but few Russians ever settled in Alaska. In the aftermath of the Crimean War, Emperor Alexander II of Russia began exploring the possibility of selling Alaska, which would be difficult to defend in any future war from being conquered by its main arch-rival, the United Kingdom. Following the end of the American Civil War, U.S. Secretary of State William Seward entered into negotiations with Russian minister Eduard de Stoeckl for the purchase of Alaska. Seward and Stoeckl agreed to a treaty on March 30, 1867, and the treaty was ratified by the United States Senate by a wide margin despite clashes between President Andrew Johnson and Congress over Reconstruction.

The purchase added 586,412 square miles (1,518,800 km2) of new territory to the United States for the cost of $7.2 million (2 cents per acre). In modern terms, the cost was equivalent to $132 million in 2019 dollars or $0.37 per acre.Reactions to the purchase in the United States were mostly positive, as many believed possession of Alaska would serve as a base to expand American trade in Asia. Some opponents labeled the purchase as "Seward's Folly", or "Seward's Icebox",as they contended that the United States had acquired useless land. Nearly all Russian settlers left Alaska in the aftermath of the purchase; Alaska would remain sparsely populated until the Klondike Gold Rush began in 1896. Originally organized as the Department of Alaska, the area was renamed the District of Alaska and the Alaska Territory before becoming the modern State of Alaska in 1959.

18 October - The United States takes possession of Puerto Rico from Spain in 1898

 

The history of Puerto Rico began with the settlement of the archipelago of Puerto Rico by the Ortoiroid people between 3,000 and 2,000 BC. Other tribes, such as the Saladoid and Arawak Native Puerto Ricans, populated the island between 430 BC and 1000 AD. At the time of Christopher Columbus's arrival in the New World in 1493, the dominant indigenous culture was that of the Taínos. The Taíno people's numbers went dangerously low during the later half of the 16th century because of new infectious diseases carried by Europeans, exploitation by Spanish settlers, and warfare.

In 1898, during the Spanish–American War, Puerto Rico was invaded and subsequently became a possession of the United States. The first years of the 20th century were marked by the struggle to obtain greater democratic rights from the United States.

The Foraker Act of 1900 established a civil government, ending rule by American generals and the Department of War. A United States Supreme Court ruling Ortega v. Lara, 202 U.S. 339, 342 (1906),involving the Foraker Act and referring to the island as "the acquired country", soon affirmed that the Constitution of the United States applied within its territory and that any domestic Puerto Rican laws which did not conflict with the United State Constitution remained in force.

The Jones Act of 1917, which made Puerto Ricans U.S. citizens, paved the way for the drafting of Puerto Rico's Constitution and its approval by Congress and Puerto Rican voters in 1952. However, the political status of Puerto Rico, a Commonwealth controlled by the United States, remains an anomaly.

The 45-star flag, used by the United States during the invasion of Puerto Rico, was also the official flag of Puerto Rico from 1899 to 1908.

US Flag was hosted over San Juan on October 18, 1898.