Question: In what year did the conflict the Battle of Khafji was part of start?

full_context: Document 1: Gulf War: The Gulf War (2 August 1990 -- 28 February 1991), codenamed Operation Desert Shield (2 August 1990 -- 17 January 1991) for operations leading to the buildup of troops and defense of Saudi Arabia and Operation Desert Storm (17 January 1991 -- 28 February 1991) in its combat phase, was a war waged by coalition forces from 35 nations led by the United States against Iraq in response to Iraq's invasion and annexation of Kuwait.
Document 2: 1973 oil crisis: On October 6, 1973, Syria and Egypt, with support from other Arab nations, launched a surprise attack on Israel, on Yom Kippur. This renewal of hostilities in the Arab–Israeli conflict released the underlying economic pressure on oil prices. At the time, Iran was the world's second-largest oil exporter and a close US ally. Weeks later, the Shah of Iran said in an interview: "Of course [the price of oil] is going to rise... Certainly! And how!... You've [Western nations] increased the price of the wheat you sell us by 300 percent, and the same for sugar and cement... You buy our crude oil and sell it back to us, refined as petrochemicals, at a hundred times the price you've paid us... It's only fair that, from now on, you should pay more for oil. Let's say ten times more."
Document 3: Gulf War: The next targets were command and communication facilities. Saddam Hussein had closely micromanaged Iraqi forces in the Iran–Iraq War, and initiative at lower levels was discouraged. Coalition planners hoped that Iraqi resistance would quickly collapse if deprived of command and control.
Document 4: Military history of the United States: After the lengthy Iraq disarmament crisis culminated with an American demand that Iraqi President Saddam Hussein leave Iraq, which was refused, a coalition led by the United States and the United Kingdom fought the Iraqi army in the 2003 invasion of Iraq. Approximately 250,000 United States troops, with support from 45,000 British, 2,000 Australian and 200 Polish combat forces, entered Iraq primarily through their staging area in Kuwait. (Turkey had refused to permit its territory to be used for an invasion from the north.) Coalition forces also supported Iraqi Kurdish militia, estimated to number upwards of 50,000. After approximately three weeks of fighting, Hussein and the Ba'ath Party were forcibly removed, followed by 9 years of military presence by the United States and the coalition fighting alongside the newly elected Iraqi government against various insurgent groups.
Document 5: War on Terror: Following the ceasefire agreement that suspended hostilities (but not officially ended) in the 1991 Gulf War, the United States and its allies instituted and began patrolling Iraqi no-fly zones, to protect Iraq's Kurdish and Shi'a Arab population—both of which suffered attacks from the Hussein regime before and after the Gulf War—in Iraq's northern and southern regions, respectively. U.S. forces continued in combat zone deployments through November 1995 and launched Operation Desert Fox against Iraq in 1998 after it failed to meet U.S. demands of "unconditional cooperation" in weapons inspections.
Document 6: Battle of the Bridges: The Battle of the Bridges or Kuwaiti Bridges (), also known as the Battle of Jal al Atraf, was a battle that took place on 2 August 1990, in Kuwait following the Iraqi invasion of Kuwait.
Document 7: Invasion of Kuwait: The Invasion of Kuwait on 2 August 1990 was a two - day operation conducted by Iraq against the neighboring state of Kuwait, which resulted in the seven - month - long Iraqi occupation of the country. This invasion and Iraq's subsequent refusal to withdraw from Kuwait by a deadline mandated by the United Nations led to military intervention by a United Nations - authorized coalition of forces led by the United States. These events came to be known as the first Gulf War and resulted in the expulsion of Iraqi forces from Kuwait and the Iraqis setting 600 Kuwaiti oil wells on fire during their retreat.
Document 8: Battle of Khafji: The Battle of Khafji was the first major ground engagement of the Persian Gulf War. It took place in and around the Saudi Arabian city of Khafji, from 29 January to 1 February 1991 and marked the culmination of the Coalition's air campaign over Kuwait and Iraq, which had begun on 17 January 1991.
Document 9: War in Afghanistan (2001–present): The War in Afghanistan (or the U.S. War in Afghanistan; code named Operation Enduring Freedom -- Afghanistan (2001 -- 2014) and Operation Freedom's Sentinel (2015 -- present)) followed the United States invasion of Afghanistan of October 7, 2001. The U.S. was supported initially by the United Kingdom and Canada and later by a coalition of over 40 countries, including all NATO members. The war's public aims were to dismantle al - Qaeda and to deny it a safe base of operations in Afghanistan by removing the Taliban from power. The War in Afghanistan is the second longest war in United States history, behind the Vietnam War.
Document 10: War on Terror: The first ground attack came at the Battle of Umm Qasr on 21 March 2003 when a combined force of British, American and Polish forces seized control of the port city of Umm Qasr. Baghdad, Iraq's capital city, fell to American forces in April 2003 and Saddam Hussein's government quickly dissolved. On 1 May 2003, Bush announced that major combat operations in Iraq had ended. However, an insurgency arose against the U.S.-led coalition and the newly developing Iraqi military and post-Saddam government. The insurgency, which included al-Qaeda affiliated groups, led to far more coalition casualties than the invasion. Other elements of the insurgency were led by fugitive members of President Hussein's Ba'ath regime, which included Iraqi nationalists and pan-Arabists. Many insurgency leaders are Islamists and claim to be fighting a religious war to reestablish the Islamic Caliphate of centuries past. Iraq's former president, Saddam Hussein was captured by U.S. forces in December 2003. He was executed in 2006.
Document 11: Gulf War: The Gulf War (2 August 199028 February 1991), codenamed Operation Desert Shield (2 August 199017 January 1991) for operations leading to the buildup of troops and defense of Saudi Arabia and Operation Desert Storm (17 January 199128 February 1991) in its combat phase, was a war waged by coalition forces from 35 nations led by the United States against Iraq in response to Iraq's invasion and annexation of Kuwait arising from oil pricing and production disputes. The war is also known under other names, such as the Persian Gulf War, First Gulf War, Gulf War I, Kuwait War, First Iraq War or Iraq War, before the term "Iraq War" became identified instead with the post-2003 Iraq War.
Document 12: Gulf War: The war is also known under other names, such as the Persian Gulf War, First Gulf War, Gulf War I, Kuwait War, First Iraq War or Iraq War, before the term ``Iraq War ''became identified instead with the 2003 Iraq War (also referred to in the US as`` Operation Iraqi Freedom''). The Iraqi Army's occupation of Kuwait that began 2 August 1990 was met with international condemnation and brought immediate economic sanctions against Iraq by members of the UN Security Council. US President George H.W. Bush deployed US forces into Saudi Arabia, and urged other countries to send their own forces to the scene. An array of nations joined the coalition, the largest military alliance since World War II. The great majority of the coalition's military forces were from the US, with Saudi Arabia, the United Kingdom and Egypt as leading contributors, in that order. Kuwait and Saudi Arabia paid around US $32 billion of the US $60 billion cost.
Document 13: Islamism: Another factor in the early 1990s that worked to radicalize the Islamist movement was the Gulf War, which brought several hundred thousand US and allied non-Muslim military personnel to Saudi Arabian soil to put an end to Saddam Hussein's occupation of Kuwait. Prior to 1990 Saudi Arabia played an important role in restraining the many Islamist groups that received its aid. But when Saddam, secularist and Ba'athist dictator of neighboring Iraq, attacked Saudi Arabia (his enemy in the war), western troops came to protect the Saudi monarchy. Islamists accused the Saudi regime of being a puppet of the west.
Document 14: Gulf War: The war is also known under other names, such as the Persian Gulf War, First Gulf War, Gulf War I, Kuwait War, First Iraq War or Iraq War, before the term ``Iraq War ''became identified instead with the 2003 Iraq War (also referred to in the US as`` Operation Iraqi Freedom''). The Iraqi Army's occupation of Kuwait that began 2 August 1990 was met with international condemnation and brought immediate economic sanctions against Iraq by members of the UN Security Council. Together with the UK's prime minister Margaret Thatcher (who had fiercely resisted the invasion by Argentina of the Falkland Islands a decade earlier), George Bush deployed US forces into Saudi Arabia, and urged other countries to send their own forces to the scene. An array of nations joined the coalition, forming the largest military alliance since World War II. The great majority of the coalition's military forces were from the US, with Saudi Arabia, the United Kingdom and Egypt as leading contributors, in that order. Kuwait and Saudi Arabia paid around US $32 billion of the US $60 billion cost.
Document 15: United States Army: By 1989 Germany was nearing reunification and the Cold War was coming to a close. Army leadership reacted by starting to plan for a reduction in strength. By November 1989 Pentagon briefers were laying out plans to reduce army end strength by 23%, from 750,000 to 580,000. A number of incentives such as early retirement were used. In 1990 Iraq invaded its smaller neighbor, Kuwait, and U.S. land forces, quickly deployed to assure the protection of Saudi Arabia. In January 1991 Operation Desert Storm commenced, a U.S.-led coalition which deployed over 500,000 troops, the bulk of them from U.S. Army formations, to drive out Iraqi forces. The campaign ended in total victory, as Western coalition forces routed the Iraqi Army, organized along Soviet lines, in just one hundred hours.
ground_truth: 2 August 1990
sub_queries: Battle of Khafji >> part of Answer: Gulf War
What year did Gulf War start? Answer: 2 August 1990