Question: Which happened first, The Battle of Gettysburg or The Western Allied invasion of Germany?

Context paragraphs:
Western Allied invasion of Germany: The Western Allied invasion of Germany was coordinated by the Western Allies during the final months of hostilities in the European theatre of World War II.  The Allied invasion of Germany started with the Western Allies crossing the Rhine River in March 1945 before fanning out and overrunning all of western Germany from the Baltic in the north to Austria in the south before the Germans surrendered on 8 May 1945.  This is known as the "Central Europe Campaign" in United States military histories.

Battle of Gettysburg: The Battle of Gettysburg ( , with an sound) was fought July 1–3, 1863, in and around the town of Gettysburg, Pennsylvania, by Union and Confederate forces during the American Civil War.  The battle involved the largest number of casualties of the entire war and is often described as the war's turning point.  Union Maj. Gen. George Meade's Army of the Potomac defeated attacks by Confederate Gen. Robert E. Lee's Army of Northern Virginia, halting Lee's invasion of the North.

Matthew Ridgway: General Matthew Bunker Ridgway (March 3, 1895 – July 26, 1993) was the 19 Chief of Staff of the United States Army.  He served with great distinction during World War II, where he was the Commanding General (CG) of the 82nd Airborne Division, leading it in action in Sicily, Italy and Normandy, before taking command of the newly formed XVIII Airborne Corps in August 1944, holding this post until the end of the war, commanding it in the Battle of the Bulge, Operation Varsity and the Western Allied invasion of Germany.

Arthur Tedder, 1st Baron Tedder: Marshal of the Royal Air Force Arthur William Tedder, 1st Baron Tedder, {'1': ", '2': ", '3': ", '4': "} (11 July 1890 – 3 June 1967) was a senior Royal Air Force commander.  He was a pilot and squadron commander in the Royal Flying Corps in the First World War and he went on to serve as a senior officer in the Royal Air Force during the inter-war years when he served in Turkey, Great Britain and the Far East.  During the Second World War, as Air Officer Commanding RAF Middle East Command, Tedder directed air operations in the Mediterranean and North Africa, including the evacuation of Crete and "Operation Crusader" in North Africa.  His bombing tactics became known as the "Tedder Carpet".  Later in the war Tedder took command of Mediterranean Air Command and in that role was closely involved in the planning of the Allied invasion of Sicily and then the Allied invasion of Italy.  When Operation Overlord—the invasion of France—came to be planned, Tedder was appointed Deputy Supreme Commander at Supreme Headquarters Allied Expeditionary Force under General Eisenhower.  After the war he served as Chief of the Air Staff, in which role he advocated increased recruiting in the face of many airmen leaving the service, doubled the size of RAF Fighter Command and implemented arrangements for the Berlin Airlift in 1948.  After the war he held senior positions in business and academia.

Allied invasion of Italy order of battle: Allied Invasion of Italy Order of Battle is a listing of the significant Allied and Axis formations that were involved during the Allied invasion of Italy (the landings at Salerno, Reggio and Taranto) 3 September – 16 September 1943.

Normandie-Niemen: The Normandie-Niemen Regiment (Russian: Нормандия-Неман ) is a fighter squadron, later regiment (of three squadrons) of the French Air Force.  It served on the Eastern Front of the European Theatre of World War II with the 1st Air Army.  The regiment is notable for being one of only three units from Western Allied countries to see combat on the Eastern Front during World War II, and "Normandie-Niemen" was the only Western Allied unit to fight with the Soviet forces until the end of the war in Europe.

21st Army Group: The 21st Army Group was a World War II British headquarters formation, in command of two field armies and other supporting units, consisting primarily of the British Second Army and the First Canadian Army.  Established in London during July 1943, under the command of Supreme Headquarters Allied Expeditionary Force (SHAEF), it was assigned to Operation Overlord, the Western Allied invasion of Europe, and was an important Allied force in the European Theatre.  The 21st Army Group operated in Northern France, Luxembourg, Belgium, the Netherlands and Germany from June 1944 until the end of the war in Europe in May 1945, after which it was redesignated the British Army of the Rhine (BAOR).

Algernon Willis: Admiral of the Fleet Sir Algernon Usborne Willis (17 May 1889 – 12 April 1976) was a Royal Navy officer.  He served in the First World War and saw action at the Battle of Jutland in May 1916.  He also served in the Second World War as Commander-in-Chief, South Atlantic in which capacity he led actions against German and Japanese raiding ships.  He continued his war service as Flag Officer commanding 3rd Battle Squadron and Second in command of the Eastern Fleet and then as Flag Officer commanding Force H, the force which covered North African Operations, the Allied invasion of Sicily in July 1943 and then the Allied invasion of Italy in September 1943.  He spent the final years of the war as Commander-in-Chief, Levant, in which capacity he conducted naval operations in support of the Dodecanese Campaign, and then as Second Sea Lord, in which capacity he arranged the manpower for the campaign in the Pacific Ocean against the Imperial Japanese Navy.  After the war he served as Commander-in-Chief, Mediterranean Fleet, in which role he was faced with unrest in Mandatory Palestine, before he became Commander-in-Chief, Portsmouth.

Gettysburg Spring Railroad: The Gettysburg Spring Railroad (Springs Horse Railway) was a Gettysburg Battlefield tourist conveyance in the Battle of Gettysburg, First Day, area.  The trolley extended from the western terminus on the east side of Herr Ridge at the Gettysburg Springs Hotel eastward to the Gettysburg borough after crossing Willoughby Run, McPherson Ridge, Pitzer Run, Seminary Ridge, Stevens Run (stone bridge), to the slopes of Baltimore Hill where it turned northward at the borough square to end at the Gettysburg Railroad Station.  In addition to a stop at the Lutheran Theological Seminary at Gettysburg, by 1879 the horse railroad had a stop near Pitzer Run at the "" which was replaced after 1904 with a horse track east of Stevens Run at the county fairgrounds (now the Gettysburg Recreation Park).

Arthur Power: Admiral of the Fleet Sir Arthur John Power (12 April 1889 – 28 January 1960) was a Royal Navy officer.  He took part in the First World War as a gunnery officer and saw action in the Dardanelles Campaign.  During the inter-war years he commanded the gunnery school at HMS "Excellent" and then the aircraft carrier HMS "Ark Royal" .  During the Second World War he played a leading role in the planning for the Allied invasion of Sicily and for the Allied invasion of Italy and then commanded the naval forces for the actual landing of V Corps at Taranto in Italy in September 1943.  He went on to be Commander-in-Chief of the East Indies Fleet in the closing stages of the war and conducted naval strikes on the Imperial Japanese Army in Borneo and Malaya.  After the War he became Second Sea Lord and Chief of Naval Personnel, Commander-in-Chief, Mediterranean Fleet and then Commander-in-Chief, Portsmouth.

Supporting paragraphs: Battle of Gettysburg Western Allied invasion of Germany
Answer: The Battle of Gettysburg