Poland, formally the Republic of Poland, is a Central European nation. It is organized into 16 administrative provinces known as voivodeships and has a total size of 312,696 km2 (120,733 sq mi). Poland is the fifth-most populated member state of the European Union, with a population of over 38 million people. Warsaw is Poland's capital and biggest city. Kraków, ód, Wrocaw, Pozna, Gdask, and Szczecin are other important cities.
Poland's landmass stretches from the Baltic Sea to the Sudeten and Carpathian Mountains in the south. Lithuania and Russia border the nation to the northeast, Belarus and Ukraine to the east, Slovakia and the Czech Republic to the south, and Germany to the west. Poland has maritime borders with Denmark and Sweden.
Human activity on Polish land dates back thousands of years. It became very diversified throughout the late antiquity era, with many civilizations and tribes settling on the huge Central European Plain. The Polans, on the other hand, ruled the area and gave Poland its name. The creation of Polish sovereignty may be traced back to 966, when the pagan monarch of a kingdom including modern-day Poland accepted Christianity and converted to Catholicism. The Kingdom of Poland was established in 1025 and signed the Union of Lublin in 1569, cementing its long-standing political relationship with Lithuania. The latter resulted in the formation of the Polish–Lithuanian Commonwealth, one of Europe's biggest and most populous states in the 16th and 17th centuries, with a distinctively liberal political system that adopted Europe's first modern constitution, the Constitution of 3 May 1791.
At the close of the 18th century, with the end of the affluent Polish Golden Age, the nation was partitioned by neighboring powers. With the Treaty of Versailles, it recovered its independence and re-established itself as a vital participant in European affairs. The German-Soviet invasion of Poland in September 1939 marked the start of World War II, which ended in the Holocaust and millions of Polish fatalities. In the midst of global Cold War tensions, the Polish People's Republic declared itself an immediate signatory of the Warsaw Pact as an Eastern Bloc member. The communist regime was abolished in the aftermath of the 1989 events, especially via the rise and contributions of the Solidarity movement, and Poland re-established itself as a democratic republic.
Poland is a developed market and a middle power, with the sixth biggest nominal GDP and fifth largest GDP in the European Union (PPP). It has exceptionally high living standards, security, and economic independence, as well as free university education and a universal health care system. The nation is home to 17 UNESCO World Heritage Sites, 15 of which are cultural in nature. Poland is a United Nations founding member, as well as a member of the World Trade Organization, NATO, and the European Union (including the Schengen Area).