It is a private mercenary organisation came in to existence in 2014 during Russian annexation of Crimea. Apart from Ukraine it has footprints across Africa and West Asia.
It is essentially a network of contractors that supply soldiers for hire and the group got registered as company in 2022.
The skull is the symbol of the Wagner group. The organization first came to the world’s attention in 2014 fighting alongside Russian backed separatists in the Donbas region of eastern Ukraine.
What is the issue:
Putin sends Wagner mercenaries group to Ukraine war. The chief of the Wagner group wants more money and they have also operational problems with Russian army so he decided to return from Ukraine and seize Moscow.
However, later he arrived at compromise with Russian government.
Lessons from the past:
Medieval Roman and European kings had used mercenaries to fight the war and often at last moment the mercenary would change the alliance to the highest bidder and the outcome changed.
So excess reliance on mercenaries is usually failure for example in 1961 USA using Cuban exiled as mercenary to overthrow Fidel Castro govt., was failure effort. Despite such lessons from history Putin used Wagner mercenaries in Ukraine.
There should be purity of means to achieve goals:
Mercenaries do not have any patriotism. They will fight for highest bidder.
Wagner owner known to be corrupt person who was jailed 9 years for robbery yet Putin used such criminal to fight in Ukraine war.
Therefore, it is difficult to expect success, loyalty, patriotism and ethical behaviour from such paid mercenaries.