The United Islamic Republic (UIR; Arabic: ; Persian: ) is a republic situated in the Middle East, ruled as a Islamic single-party state with Tehran as its capital and largest city. It shares borders with the Eurasian Union and the European Federation to the north, the United Arab Republic to the west and northwest, Jordan to the west, Pakistan and India to the east, Yemen, Oman, and Qatar to the south and southeast, and shares maritime borders with Bahrain. At 4,252,777 km2 (1,682,486 square miles), the United Islamic Republic is the world's seventh largest country by area, and the fifth largest country in the world by population with almost 220 million people. The UIR possesses the world's second largest reserves of energy resources, and is the largest exporter of oil and the second largest exporter of natural gas in the world. It is also the world's second largest producer of oil.

In 1996, an Iranian agent, Ayatollah Mahmoud Haji Daryaei, assassinated the president of Iraq, Saddam Hussein, and took advantage of the power vacuum by launching an unopposed invasion of Iraq. The ayatollah united Iraq and Iran into the United Islamic Republic (UIR). With assistance of the Eurasian Union, People's Republic of China and India, the UIR made a bid for superpower status by attacking Saudi Arabia. Following a series of Iranian-backed terrorist attacks—including the release of a genetically-enhanced Ebola strain—the UIR declared war on both Saudi Arabia and Kuwait, and launched the Second Persian Gulf War, later joined by the United Arab Republic (UIR). The ayatollah fielded over 1,500,000 Iranian-Iraqi soldiers equipped with heavy weapons, 6,500 tanks, and over 3,000 aircraft. The UIR and UAR succesfully invaded Saudi Arabia by blitzkrieg tactics, and advanced into Kuwait. The Iranian-Iraqi air force destroyed most of the Kuwaiti Air Force, before the army could launch their invasion. The United States, led by President Jack Ryan declared martial law and enforced travel restrictions in an effort to contain the virus. A combined Coalition led by the U.S. invaded Saudi Arabia to stop the UIR, but were driven back by combined UIR, Syrian and Egyptian forces. The Second Persian Gulf War ended with a decisive UIR and UAR victory, and the U.S. finally forced to recognize the United Islamic Republic.

A major economic power, the United Islamic Republic has emerged as the largest national economy in the Arab world, and is the fourth largest national economy in the world. UIR's petroleum industry is the second largest in the world after the Eurasian petroleum industry. The United Islamic Republic is a recognized superpower, with the world's fourth largest military force, and possesses the third largest stockpile of weapons of mass destruction. Its air force and navy are among the world's five largest.