A WWII Grand strategy game
Hearts of Iron is, like most Paradox Development Studio titles, a grand strategy game in an open sandbox. The World War II theme does mean that there is a lot greater focus on the preparation for war, your industrial output and military doctrines and equipment. But in Hearts of Iron IV, you are dealing with the bigger picture and a very high level of strategic planning; this is not a pure old-fashioned wargame. Losing small battles is utterly insignificant to the larger campaign. You have to look at the entire war and take decisions in a multiple of aspects to reach victory - this is truly high level war planning, including production lines, technological advances, securing strategic resources and, of course, making those large armored drives through the plains of Europe.

Comparison to other PDS titles
The big thing that sets it apart from our other game series such as Crusader Kings II and Europa Universalis IV is that it covers a much shorter period of time, namely the years around the Second World War and that it focuses heavily on preparing for and fighting that war. This means that your priorities will largely stay the same throughout the game – your are unlikely to make a dramatic change from one kind of nation to another. You can pick any nation in the world and either ride out the storm on the sidelines, get involved in the grand cataclysm, or try something a little bit in-between. Hearts of Iron is packed full of historical flavor and awesome details, something much harder to accomplish in games spanning hundreds of years.

However even if Hearts of Iron IV is a grand strategy game highly focused on war, the role you take on as the player is close to the role you take in Europa Universalis IV - you will play as the guiding spirit behind the nation trying to shape history and determine the fate of your country, often guided by in-game events and decisions. The game focuses on making choices for your nation, both in warfare as in the character of your country’s technological progress, national ideas and strategic goals. You can pick any nation and decide what role you will take in WW2.

You can choose different play styles depending on your personal interest or based on the different strengths and weaknesses of the historic powers. For example, as Germany you have an incentive to start the war, while the UK and US will likely start on the defensive and will fight massive naval battles. You can even try to survive as a minor nation, whose government continues fighting from exile or be a smaller power taking advantage of the global war to expand your rightful territory. Nothing that says that your goal must be to win WWII - since the game is sandbox, victory is determined by the goals you set up for yourself during the WWII time-span.