Question: Which operation began first, Spring 1945 offensive in Italy or Operation Overlord?

Context paragraphs:
LXXVI Panzer Corps: The LXXVI Panzer Corps ("LXXVI Panzerkorps", 76th Armoured Corps) was a panzer corps of Nazi Germany during World War II.  The headquarters were formed in France under Army Group D on 29 June 1943 as LXXVI Army Corps but renamed a month later.  In August it shipped to Italy to become part of 10th Army.  It spent the rest of the war in Italy fighting in the Italian Campaign mainly under 10th Army but with short periods from February 1944 (Battle of Anzio) and January 1945 (Spring 1945 offensive in Italy) under 14th Army.  The Corps was commanded for most of its active fighting by General Traugott Herr.

Battle of Bologna: The Battle of Bologna was fought in Bologna, Italy from 9–21 April 1945 during the Second World War, as part of the Spring 1945 offensive in Italy.  The Allied forces were victorious, with the Polish II Corps and supporting Allied units capturing the city on 21 April.

Operation Overlord: Operation Overlord was the codename for the Battle of Normandy, the Allied operation that launched the successful invasion of German-occupied Western Europe during World War II.  The operation was launched on 6 June 1944 with the Normandy landings (Operation Neptune, commonly known as D-Day).  A 1,200-plane airborne assault preceded an amphibious assault involving more than 5,000 vessels.  Nearly 160,000 troops crossed the English Channel on 6 June, and more than two million Allied troops were in France by the end of August.

Operation Charnwood: Operation Charnwood was an Anglo-Canadian offensive that took place from 8 to 9 July 1944, during the Battle for Caen, part of the larger Operation Overlord (code-name for the Battle of Normandy), in the Second World War.  The operation was intended to at least partially capture the German-occupied city of Caen (] ), which was an important objective for the Allies during the opening stages of Overlord.  It was also hoped that the attack would forestall the transfer of German armoured units from the Anglo-Canadian sector to the lightly screened American sector, where a major American offensive was being planned.  The British and Canadians advanced on a broad front and by the evening of the second day had taken Caen up to the Orne and Odon rivers.

Operation Roast: Operation Roast was a military operation undertaken by British Commandos, at Comacchio lagoon in north-east Italy, during the Spring 1945 offensive in Italy, part of the Italian Campaign, during the final stages of Second World War.

Rhodesian Armoured Corps: The Rhodesian Armoured Corps—the "Black Devils"—was the only standing armoured battalion of the Rhodesian Security Forces.  During World War II, it took part in the Allied Spring 1945 offensive and the Battle of Monte Cassino as part of South Africa's 6th Armoured Division.  The unit was among the first to enter a liberated Florence in July 1944.  Prior to 1963, its crews were trained in the United Kingdom or Aden Colony and were known as the "Selous Scouts" under the Federation of Rhodesia and Nyasaland.  After Rhodesia's Unilateral Declaration of Independence, maintaining the armoured vehicle fleet became a responsibility of the Rhodesian Light Infantry until Major Bruce Rooken-Smith reactivated the former "Rhodesian Armoured Car Regiment" in 1972.  During the Rhodesian Bush War, the regiment fought in several major campaigns and battles, particularly Operation Miracle in September 1979.  It was superseded by the new "Zimbabwe Armoured Corps" between 1980 and 1981.

Spring 1945 offensive in Italy: The Spring 1945 offensive in Italy, codenamed Operation Grapeshot, was the final Allied attack during the Italian Campaign in the final stages of the Second World War.  The attack into the Lombardy Plain by the 15th Allied Army Group started on 6 April 1945, ending on 2 May with the formal surrender of German forces in Italy.

Normandy landings: The Normandy landings (codenamed Operation Neptune) were the landing operations on Tuesday, 6 June 1944 (termed D-Day) of the Allied invasion of Normandy in Operation Overlord during World War II.  The largest seaborne invasion in history, the operation began the liberation of German-occupied northwestern Europe from Nazi control, and contributed to the Allied victory on the Western Front.

Battle of the Argenta Gap: The Battle of the Argenta Gap was an engagement which formed part of the Allied spring 1945 offensive during the Italian Campaign in the final stages of the Second World War.  It took place in northern Italy from 12–19 April 1945 between troops of British V Corps commanded by Lieutenant-General Charles Keightley and German units of LXXVI Panzer Corps commanded by Lieutenant General ("General der Panzertruppe") Gerhard von Schwerin.

Operation Grapeshot order of battle: Operation Grapeshot order of battle is a listing of the significant formations that were involved in the Spring 1945 offensive in the Apennine Mountains and the Po valley in northern Italy, April 1945 – May 1945.

Supporting paragraphs: Spring 1945 offensive in Italy Operation Overlord
Answer: Operation Overlord