You need to specify what you are referring to if you want to make it possible to answer your question.
The Communist Party of The Soviet Union...
The Soviet Union is not run by anyone, since it no longer exists.The Soviet Union was run by a president in the last two years of its existence: 1990-1991. Prior to that, the Soviet Union was run by the Politburo of the Communist Party. The de facto leader of the country was the General Secretary of the Communist Party.Russia, which is political heir of the Soviet Union, is run by a president today.
For the First Bull Run, the Union commander was Major General Irvin McDowell. For the Second Bull Run, Major General John Pope led the Union armies.
The Tigris runs from Turkey through Syria and Iran to Iraq.
A Union victory was expected at the first Battle of Bull Run. It was indeed a shock to have suffered a defeat.
Through Germany, Austria, Slovakia, Hungary Serbia., Bulgaria. Moldova, Ukraine and Romania
the European Union or EU
The E.U. is run through seven institutions. These are the Council of the European Union, Court of Justice of the European Union, European Central Bank, European Commission, European Council, European Court of Auditors, and European Parliament.
Belarus, Poland, and Russia
Yes they are. They are the part of the Alps that run through Switzerland. The Alps as a whole run through a number of European countries.
The northern European plain goes through Sweden, Finland, Norway, Germany, Denmark, and a few more I can't remember on the top of my head.
There are no countries on Antarctica.
The European Parliament is a democracy, as are all the governments of major countries in Europe. Some countries do have a monarchy, but they have little power to run the country. The UK is a famous example, but also countries like Spain, Belgium, the Netherlands and Norway.
Spain !
The Volga runs through the East European Plain.
The Ural Mountains run through Russia and Kazakhstan
The Black River is in the United States, it runs through no other countries.