The airport was originally known as "Sandweiler Airport", and was opened in the 1930s as a small grass airfield with a relatively short, 3,400 ft (1,000 m) runway. Neutral Luxembourg was invaded by Germany on 10 May 1940, and on 21 May the Luftwaffe assigned Jagdgeschwader 53 (JG 53), a Messerschmitt Bf 109 fighter unit, to the airport. JG 53 was engaged in combat against the French and British Expeditionary Force in France during the Battle of France in May and June. In addition, Jagdgeschwader 52 (JG 52) operated Bf 109s from Sandweiler during the Blitzkrieg. JG 52 moved into France on 29 May but JG 53 remained in Luxembourg until 18 August when it moved closer to the English Channel to take part in the Battle of Britain. Sandweiler Airport then remained unused by the Luftwaffe until September 1944, when Aufklärungsgruppe 123 (AKG 123), a reconnaissance unit which flew the Henschel Hs 126, a two-seat reconnaissance and observation aircraft, was assigned to the airport. AKG 123 moved east into Germany after only a few days when the United States Army moved through Luxembourg and cleared the country of the occupying German forces. United States Army combat engineers arrived at Sandweiler in mid September 1944 and performed some minor reconstruction to prepare the airfield for Ninth Air Force combat aircraft. The airfield was designated as Advanced Landing Ground "A-97" Sandweiler and was opened on 18 September 1944. The Ninth Air Force 363d Tactical Reconnaissance Group operated a variety of photo-reconnaissance aircraft until 29 October 1944 when they also moved east into Germany. Sandweiler Airport was used by the Americans for the rest of the war as a transport supply airfield and also to evacuate combat casualties to the UK. It was returned to Luxembourgish control on 15 August 1945. In March 1999, Luxair launched direct flights to Newark using a Boeing 767, terminating them after only seven months of operations. In 2002, TAROM routed its flight from Bucharest to New York through Luxembourg in an attempt to increase the number of passengers. Luxembourg Airport has constructed a high-security zone far away from most airport activities in order to attract the business of transporting valuable goods such as art and jewels. According to Hiscox, there is a "massive demand" for such a hub for precious cargo. Planes taxi away from main airport facilities before loading. In 2015, the airline with the largest share of the airport's total passenger volume was still Luxair with 1.69 million passengers at a 63% share. Luxembourg Airport was closed to all passenger traffic for a week from 23 to 29 March 2020 as a public health measure during the COVID-19 pandemic. In December 2023, China Southern Airlines began service to Zhengzhou. In 2021, it was announced that public announcements in Luxembourgish (and in German as well) at Luxembourg Airport would cease after many decades of use; it would only be using French and English for future public announcements. Actioun Lëtzebuergesch declared itself to be hugely upset by this new governmental measure, citing that other airports in the world seem to have no problems making public announcements in multiple languages; according to a poll conducted by AL, 92.84% of people in Luxembourg wished to have public announcements to be made in Luxembourgish at Luxembourg Airport. All written signs at Luxembourg Airport are only in French and English. This non-use of Luxembourgish and German (two official languages of Luxembourg) have fueled claims of linguistic discrimination, some pointing out that other airports seem to have no difficulties using up to 4 different languages in written signs.