Question: Which battle took place first Operation Diadem or Battle of the Wilderness ?

Context paragraphs:
Operation Anaconda: Operation Anaconda took place in early March 2002.  CIA Paramilitary Officers, working with their allies, attempted to destroy al-Qaeda and Taliban forces.  The operation took place in the Shahi-Kot Valley and Arma Mountains southeast of Zormat.  This operation was the first large-scale battle in the United States War in Afghanistan since the Battle of Tora Bora in December 2001.  This was the first operation in the Afghanistan theater to involve a large number of U.S. conventional (i.e. non-Special Operations Forces) forces participating in direct combat activities.

Battle of Kuwait International Airport: The Battle of Kuwait International Airport occurred on February 27, 1991 during the 1st Gulf War.  It was a tank battle between the United States and Ba'athist Iraq.  Despite being a very large battle it is often overlooked compared to the other battles which took place during the war.  No less than elements of 18 divisions total participated in this battle.  U.S. Army Special Forces units and multiple Iraqi Commando units were also in theatre.  In reality the battle took place over a span of three days despite the primary battle at Kuwait International Airport lasting only one day.  Much of the combat actually took place en route to the airport.  The battle featured the "Reveille Engagement" which went on to become the biggest and fastest tank battle in United States Marine Corps' entire history.

Battle of Dalrigh: The Battle of Dalrigh, also known as the Battle of Dail Righ, Battle of Dalry or Battle of Strathfillan, was fought in the summer of 1306 between the army of King Robert I of Scotland against the Clan MacDougall of Argyll who were allies of Clan Comyn and the English.  It took place at the hamlet of Dalrigh (the "King's Field" in the Scottish Gaelic language) near Tyndrum in Perthshire, Scotland (not to be confused with Dalry, Ayrshire).  Bruce's army, reeling westwards after defeat by the English at the Battle of Methven, was intercepted and all but destroyed, with Bruce himself narrowly escaping capture.  The battle took place sometime between late July and early August, but the exact date is unknown.

Siege of Sevastopol (1941–42): The Siege of Sevastopol also known as the Defence of Sevastopol (Russian: Оборона Севастополя , transliteration: "Oborona Sevastopolya") or simply the Battle of Sevastopol (German: Schlacht um Sewastopol) was a military battle and a siege that took place on the Eastern Front of the Second World War.  The campaign was fought by the Axis powers of Germany, Romania, and Italy against the Soviet Union for control of Sevastopol, a port in the Crimea on the Black Sea.  On 22 June 1941 the Axis invaded the Soviet Union during Operation Barbarossa.  Axis land forces reached the Crimea in the autumn of 1941 and overran most of the area.  The only objective not in Axis hands was Sevastopol.  Several attempts were made to secure the city in October and November 1941.  A major attack was planned for late November, but heavy rains delayed the Axis attack until 17 December 1941.  Under the command of Erich von Manstein, Axis forces were unable to capture Sevastopol during this first operation.  Soviet forces launched an amphibious landing on the Crimean peninsula at Kerch in December 1941 to relieve the siege and force the Axis to divert forces to defend their gains.  The operation saved Sevastopol for the time being, but the bridgehead in the eastern Crimea was eliminated in May 1942.

Battle of the Allia: The Battle of the Allia was fought between the Senones (one of the Gallic tribes which had invaded northern Italy) and the Romans.  It was fought at the confluence of the rivers Tiber and Allia, eleven Roman miles (16 km) north of Rome.  The Romans were routed and subsequently the Senones sacked Rome.  The common date given for the battle is 390 BC.  This is based on the account of the battle by the Roman historian Livy and the Varronian Chronology, a Roman dating system.  The ancient Greek historian Polybius, who used a Greek dating system, derived the date 387/6 BC.  Plutarch wrote that the battle took place just after the summer solstice when the moon was near the full, a little more than three hundred and sixty years from the foundation of Rome.  That would be shortly after 393 BC.  Tacitus said that the battle took place the 15 before the Kalends of August, which is 18 July.

Battle of Cape Esperance: The Battle of Cape Esperance, also known as the Second Battle of Savo Island and, in Japanese sources, as the Sea Battle of Savo Island (サボ島沖海戦 ) , took place on 11–12 October 1942 in the Pacific campaign of World War II between the Imperial Japanese Navy and United States Navy.  The naval battle was the second of four major surface engagements during the Guadalcanal campaign and took place at the entrance to the strait between Savo Island and Guadalcanal in the Solomon Islands.  Cape Esperance ( ) is the northernmost point on Guadalcanal, and the battle took its name from this point.

Battle of Clitheroe: The Battle of Clitheroe was a battle between a force of Scots and English knights and men at arms which took place on 10 June 1138 during the period of The Anarchy.  The battle was fought on the southern edge of the Bowland Fells, at Clitheroe, Lancashire.  It took place in the course of an invasion of England by King David I of Scotland.  In the summer of 1138, King David split his army into two forces.  One of them, commanded by William fitz Duncan, Mormaer of Moray, marched into Lancashire.  There he harried Furness and Craven.  On 10 June, William fitz Duncan was met by a force of knights and men-at-arms.  A pitched battle took place and the result was that the English army was routed.  The battle was a prelude to the Battle of the Standard later in the summer, where the result was reversed.

Battle of the Wilderness: The Battle of the Wilderness, fought May 5–7, 1864, was the first battle of Lt. Gen. Ulysses S. Grant's 1864 Virginia Overland Campaign against Gen. Robert E. Lee and the Confederate Army of Northern Virginia in the American Civil War.  Both armies suffered heavy casualties, a harbinger of a bloody war of attrition by Grant against Lee's army and, eventually, the Confederate capital, Richmond, Virginia.  The battle was tactically inconclusive, as Grant disengaged and continued his offensive.

Battle of the Bay of Biscay: The Battle of the Bay of Biscay was a naval action that took place on 28 December 1943 during World War II as part of the Atlantic campaign.  The battle took place in the Bay of Biscay between two light cruisers of the British Royal Navy, and a destroyer and a torpedo boat flotilla of the German Kriegsmarine hoping to intercept and escort a blockade runner.  The battle was fought as part of the Allied Operation Stonewall which was to intercept German blockade runners off the west coast of France.  In the confused action that followed the two British cruisers HMS "Enterprise" and HMS "Glasgow" respectively sank "T-26", together with her sister ship "T-25" and the destroyer "Z27".

Operation Diadem: Operation Diadem, also referred to as the Fourth Battle of Monte Cassino or, in Canada, the Battle of the Liri Valley, was an offensive operation undertaken by the Allies of World War II (U.S. Fifth Army and British Eighth Army in May 1944, as part of the Italian Campaign of World War II.  "Diadem" was supported by air attacks called Operation Strangle.  The opposing force was the German 10th Army.

Supporting paragraphs: Battle of the Wilderness Operation Diadem
Answer: Battle of the Wilderness