Question: Which event took place first, Operation Undertone or the Battle of Leyte?

Context paragraphs:
Glory By Honor XIV: Glory By Honor XIV was a two night, two city professional wrestling event produced by the U.S.-based wrestling promotion Ring of Honor.  The first night of the event took place on October 23, 2015 at the Wing's Event Center in Kalamazoo, Michigan.  The second part of the event took place on October 24, 2015 at Montgomery County Fairgrounds Coliseum in Dayton, Ohio.

Volleyball at the Friendship Games: Volleyball at the Friendship Games was contested in two events.  Men's event took place at the Ciudad Deportiva in Havana, Cuba between 18 and 26 August 1984.  Women's event took place in Varna, Bulgaria between 8 and 15 July 1984.

Glory By Honor XV: Glory By Honor XV was a two night, two city professional wrestling event produced by the U.S.-based wrestling promotion Ring of Honor.  The first night of the event took place on October 14, 2016 at the Frontier Fieldhouse in Chicago Ridge, Illinois.  The second part of the event took place on October 15, 2016 at Ford Community & Performing Arts Center in Dearborn, Michigan.

Battle of Leyte: The Battle of Leyte in the Pacific campaign of World War II was the amphibious invasion of the Gulf of Leyte in the Philippines by American forces and Filipino guerrillas under the command of General Douglas MacArthur, who fought against the Imperial Japanese Army in the Philippines led by General Tomoyuki Yamashita from 17 October - 26 December 1944.  The operation code named "King Two" launched the Philippines campaign of 1944–45 for the recapture and liberation of the entire Philippine Archipelago and to end almost three years of Japanese occupation.

WWE Elimination Chamber: Elimination Chamber is a professional wrestling pay-per-view (PPV) event, produced by WWE, a professional wrestling promotion based in Connecticut.  The event was created in 2010, with its inaugural event taking place on February 21, 2010, replacing No Way Out.  Elimination Chamber is a pay-per-view (PPV) event consisting of a main event and undercard that features championship matches and other various matches.  The concept of the show was that the two main event matches were contested inside the Elimination Chamber; one of these matches typically featured the WWE Championship being defended, while the other was usually contested for the World Heavyweight Championship (the two titles were unified in December 2013).  The first Elimination Chamber event took place on February 21, 2010 and aired live on PPV.  The event's name was selected after WWE allowed fans to provide input via a survey on their official website and was chosen over Heavy Metal, Battle Chamber, Chamber of Conflict, and the original No Way Out name.  Since its origin, each event has been held in an indoor arena, with all five taking place in the United States.  In 2015, the event was replaced by Fastlane in the February pay-per-view slot.  However, the 2015 event was later announced to be streamed exclusively on the WWE Network in the United States on May 31 and was also available on PPV elsewhere.  WWE also confirmed that the newly vacant WWE Intercontinental Championship was being decided inside the Elimination Chamber.  The event did not occur in 2016, but returned in 2017 as a SmackDown branded event.

Vancouver Island Shootout: The Vancouver Island Shootout was an annual curling bonspiel started in 2011 as part of the World Curling Tour.  For the 2011–12 curling season, the event took place at the Juan de Fuca Curling Club in Colwood, British Columbia.  The men's event was held in a triple knockout format, and the women's event was held in a round robin format.  For the 2012–13 curling season and 2014–15 curling season, the event took place at the Victoria Curling Centre in Victoria, British Columbia, and both the men's and women's events were held in a triple knockout format.

2010 Internazionali BNL d'Italia: The 2010 Internazionali BNL d'Italia was a tennis tournament, being played on outdoor clay courts at the Foro Italico in Rome, Italy.  It was the 67th edition of the event and was classified as an ATP World Tour Masters 1000 event on the 2010 ATP World Tour and a Premier 5 event on the 2010 WTA Tour.  The men's event took place from April 24 to May 2, 2010 while the women's event took place from April 30 to May 8, 2010.

Operation Undertone: Operation Undertone was a large assault by the U.S. Seventh and French 1st Armies of the U.S. Sixth Army Group as part of the Allied invasion of Germany in March 1945 during World War II.

2014 Tianjin Health Industry Park: The 2014 Tianjin Health Industry Park was a professional tennis tournament played on clay courts.  It was the first edition of the tournament and part of the 2014 ATP Challenger Tour and 2014 ITF Women's Circuit, offering a total of $50,000+H (ATP) and $25,000 (ITF) in prize money.  It took place in Tianjin, China, the men's event took place from 16 to 22 June 2014 while the women's event took place from 19 to 25 May 2014.

EBSA European Under-21 Snooker Championships: The EBSA European Under-21 Snooker Championships is the premier non-professional junior snooker tournament in Europe.  The event series is sanctioned by the European Billiards & Snooker Association.  It took place first in 1997 and is held annually since then.  The event was known as the EBSA European Under-19 Snooker Championships until 2010.  In most years the winner of the tournament qualifies for the next two seasons of the World Snooker Tour and well as being awarded the Ebdon Trophy which is named in honour of former World Champion Peter Ebdon.

Supporting paragraphs: Operation Undertone Battle of Leyte
Answer: Battle of Leyte