It is 1895 and the world is in turmoil. In the decades to come, historians will reflect upon the cause of this state of affairs and many will point squarely at Charles Babbage. The perfection of first his Difference Engine, and then his Analytical Engine, gave the new scientific establishment in the Great Powers the tool they had so long needed in order to make a dramatic leap forward. The ability to make huge and repeatable sets of complex calculations revolutionized the world.
Within twenty years came the 'invention' of Cavorite, the perfection of miniaturized steam engines, electric light and motors, Radium Bricks, Arc weapons, Hydrogen and Helium Dirigibles, Road Trains, Calculating Artillery Engines, Sea and Land Dreadnoughts - the list is almost endless. Nothing is impossible when the wealth of a Great Power is coupled to the unlimited imagination of educated men of science and their engineers.
The one thing that all these marvellous advances have not brought is peace. Every Great Power has been jostling its neighbours for resources and more importantly, the latest technology. None can afford to stand still and allow its neighbours to advance their science and engineering unmolested. If they do, they risk being overwhelmed as the French were in 1861 by the Prussians' mobile Calculating Artillery Engines, or as the Union was the year after that, with their ports put to the flame and successfully blockaded by the Confederacy's Armored Sea Dreadnoughts.
Some nations have also been tapping into older, more sinister powers, in order to produce an unholy combination of the mystical and the mechanical, such as the Prussian Todt-truppen.
Although there have been relatively few open conflicts between the Great Powers, a state of undeclared and secret war exists between them all. This is where the Adventuring Companies come in. These are the deniable clandestine agents of the Great Powers (and of other globe-spanning organizations). They act in the shadows pitting their skills, their wits and the latest technologies against each other, to obtain the latest scientific formula, artefact or other vital component.
Small groups of highly skilled and specialized operatives are brought together for each mission under the command of a trusted 'Captain'. In Great Britain they work out of the Explorers' Club in London. In Prussia their patron is the highly secretive Thule Society. In the USA they are mostly sponsored by the Secret Service. There are similar organizations in each of the Great Powers. They each have the choice of their nation's latest arms, armor and other equipment with which to perform their missions.