Here are some critical facts about Lithuania:

- Lithuania is located along the southeastern shore of the Baltic Sea in northern Europe. It shares borders with Latvia, Belarus, Poland and Russia.

- Its capital and largest city is Vilnius. Lithuania has a population of about 2.8 million people. Ethnic Lithuanians comprise about 84% of the population.

- Lithuania was once one of the largest countries in Europe before losing territory to Russia and Prussia. The Soviet Union occupied it during WWII before declaring independence in 1990.

- Lithuania joined both NATO and the European Union in 2004, cementing ties with Western Europe after decades of Soviet domination. Its currency is the Euro.

- Lithuanians predominantly speak Lithuanian, though Russian and Polish minority languages have a strong presence. The main religions are Roman Catholicism and Lutheranism.

- The landscape varies between lowlands, rolling hills, and forests. Over 33,000 rivers and streams run through the country, including the Nemunas, which flows through the capital Vilnius.

- Key industries include processed foods, petroleum, machinery and electronics manufacturing, shipbuilding, furniture making, and lasers. Agriculture and tourism also contribute significantly.

In summary, Lithuania is a Baltic country formerly under Soviet control. Since gaining independence, it has oriented itself as a Central European country and has been a member of Western institutions like the EU and NATO.