Arizona states of Sonora and Baja California. Arizona is the 48th state and last of the contiguous states to be admitted to the Union, achieving statehood on February 14, 1912, coinciding with Valentine's Day. Historically part of the territory of "Alta California" in New Spain, it became part of independent Mexico in 1821. After being defeated in the Mexican–American War, Mexico ceded much of this territory to the United States in 1848. The southernmost portion of the state was acquired in 1853 through the Gadsden Purchase. Southern Arizona is known for its desert climate, with very hot summers and mild winters.
Referendums related to the European Union Croatia was admitted as a member of the EU, acceding on 1 July 2013. A referendum was held in San Marino on whether the country should submit an application to join the European Union as a full member state. The Unified Patent Court is a proposed court between several EU member states, that, inter alia, is to be constituted for litigation related to the European Union patent. Countries which seek to join the European Union in the future may hold a referendum as part of the accession process. In addition, Article 88-5 of the Constitution of France requires a referendum