Final answer:
The newest country in the European context is South Sudan by date of independence, though geographically it's in Africa. Within strictly European nations, Kosovo is one of the newest, declared in 2008, but with partial international recognition. The latest country to join the EU is Croatia in 2013.
Step-by-step explanation:
The newest country in Europe is South Sudan, which declared independence from Sudan on July 9, 2011. However, it's critical to note that while South Sudan is geographically located in the northeastern part of Africa, its admission into international organizations such as the United Nations has at times placed it in alignment with the Group of Eastern European States due to its political associations. In the context of strictly European nations, Kosovo could be considered one of the newest countries, having declared independence from Serbia in 2008, but it is not universally recognized with some major international bodies and countries still not acknowledging its sovereignty.
In the context of European Union (EU) expansion, the latest member to join was Croatia in 2013. It's important to mention that the status of countries, territories, and regions can be complex and the recognition of a state's sovereignty may vary internationally. The EU after the United Kingdom's withdrawal, known as Brexit, now comprises 27 member countries.