In Hearts Of Iron IV history can be fully relived or rewritten from the perspective of a global superpower attempting to change the world, or a small nation simply trying to survive. World War II is at your fingertips as you guide your nation, plan your research, build you forces and design sweeping battle plans that will put the world at your feet.

Take control of any nation in the world and guide it through humanity’s most trying hours. With a new and improved battleplan system, you will be able to direct sweeping movements of troops through steppes, deserts and jungles. Area and mission based systems take the micromanagement out of naval and air combat. Strategy fans will discover the most authentic real-time simulation of World War II to date, with authentic historical figures battling on land, sea, and air with period-accurate armies, vehicles, and newly discovered weapons of mass destruction – along with plenty of diplomatic and trade tactics.

The global crisis reaches all corners of the map. No one is safe from the ambitions and appetites of empire builders. Defend Southeast Asia from growing threats in Hearts of Iron IV: Thunder At Our Gates, a new Theater Pack for Paradox Interactive’s best-selling strategy wargame about the years around World War II.

Coming on 11 June, Thunder At Our Gates adds new national focus trees for key nations in Asia and the South Pacific, including Australia, Siam and the Dutch East Indies. Use your resources to turn your minor powers into mighty fortresses, able to hold off distant but hungry nations or carve out your own empire. This pack also includes two new ways to organize and empower your military forces.

Features of Hearts of Iron IV: Thunder At Our Gates include:

• New Australian Content: 
  • Balance the domestic needs of a nation still reeling from the Great Depression against the demands of a British alliance still valued by much of the population.
  • Influence the course of elections to deal with current priorities.
  • Navigate treacherous political waters following the Canberra Air Disaster.
  • Face the challenges presented by a small and scattered population while at war.
  • Develop Australia’s rich natural resources.
  • Follow alternate historical paths of Australia First nationalism or anti-war Communism.
• New Siamese Focus Tree: 
  • Balance or choose between civilian and military domination of the government, pushing for constitutional safeguards or a military coup.
  • Industrialize Siam, expanding national teak and rubber reserves while developing road and rail infrastructure.
  • Submit to foreign domination, saving strength for a later date, or resist the imperial powers.
  • Prospect for new resources to fuel your developing nation.
  • Conquer your neighbors and embrace the traditional path of the old Rattanakosin Kingdom of your ancestors.
• New Dutch East Indian Content: 
  • Develop a wartime economy based on rich and valuable rubber and oil reserves to overcome your lack of factories.
  • Pursue autonomy from the Netherlands following the Soetardjo Petition or stay loyal to the Dutch crown.
  • Explore special military focus trees to demonstrate co-operation between Dutch and East Indian forces.
  • If Occupied, take advantage of Japanese decline and seize the initiative to pursue revolution and independence.
• Ship Captains: Divisional commanders are now available for the naval game in the form of Ship Captains. Award them medals to improve their performance, and promote them to Admirals to lead your fleets to victory.
• Army Headquarters. Deploy Generals to the field to greatly enhance the performance of nearby units, but with the risk of capture in the field. Imprisoned generals can be liberated through a new Raid option.

This Theater Pack will be accompanied by a free update that includes many game changes, including the Regimental Support feature, introducing new ways to attach support units to your divisions, including several new regimental support companies.

Hearts of Iron IV: Thunder At Our Gates will be available on 11 June 2026 for the suggested retail price of $19.99/£16.75 /€19.99.