Question: What battles took place in the forest controlled during Operation Clipper?

Context paragraphs:
The Fifteen Decisive Battles of the World: The Fifteen Decisive Battles of the World: from Marathon to Waterloo is a book written by Sir Edward Shepherd Creasy and published in 1851.  This book tells the story of the fifteen military engagements, which, according to the author, had a significant impact on world history.  The selection reflects the worldview of a 19th-century European with a classical education: fourteen of the battles took place in the arc of historically interconnected military theatres which stretched from Persia through the Mediterranean Basin to Europe, and one was fought by European powers and former colonies in North America.

Battles of Kawanakajima: The battles of Kawanakajima (川中島の戦い , Kawanakajima no tatakai ) were fought in the Sengoku period of Japan between Takeda Shingen of Kai Province and Uesugi Kenshin of Echigo Province in the plain of Kawanakajima, "the island between the rivers", in the north of Shinano Province.  The location is in the southern part of the present-day city of Nagano.  Five major battles took place there: Fuse in 1553, Saigawa in 1555, Uenohara in 1557, Hachimanbara in 1561, and Shiozaki in 1564.  The best known and most severe among them was fought on October 18, 1561, and was only fought in the heart of the Kawanakajima plain, thus being "the" "battle of Kawanakajima".  The battles were fought after Shingen conquered Shinano, expelling Ogasawara Nagatoki and Murakami Yoshikiyo, who subsequently turned to Kenshin for help.  The battles became one of the most cherished tales in Japanese military history, the epitome of Japanese chivalry and romance, mentioned in epic literature, woodblock printing and movies.

Battle of Hürtgen Forest: The Battle of Hürtgen Forest (German: "Schlacht im Hürtgenwald" ) was a series of fierce battles fought from 19 September to 16 December 1944 between American and German forces on the Western Front during World War II in the Hürtgen Forest about 50 mi2 east of the Belgian–German border.  It was the longest battle on German ground during World War II, and is the longest single battle the U.S. Army has ever fought.

Fourth Encirclement Campaign: The Fourth Encirclement Campaign is an abbreviated name used for several different encirclement campaigns launched by the Nationalist Government with the goal of destroying the developing Chinese Red Army and its communist bases.  The battles took place in several separate locations in China during the early stage of Chinese Civil War, between the late 1920s to mid-1930s.  These are:

Poitiers: Poitiers (] ) is a city on the Clain river in west-central France.  It is a commune and the capital of the Vienne department and also of the Poitou.  Poitiers is a major university centre.  The centre of town is picturesque and its streets include predominantly historical architecture, especially religious architecture and especially from the Romanesque period.  Two major military battles took place near the city: in 732, the Battle of Poitiers (also known as the Battle of Tours), in which the Franks commanded by Charles Martel halted the expansion of the Umayyad Caliphate, and in 1356, the Battle of Poitiers, a key victory for the English forces during the Hundred Years' War.  This battle's consequences partly provoked the Jacquerie.

Operation Clipper: During the Second World War, Operation Clipper was an Allied offensive by British XXX Corps (which included the U.S. 84th Infantry Division) to reduce the Geilenkirchen salient in mid-November 1944.  "Clipper" was the preliminary to the wider Allied operation, named Operation Queen to gain control of the Roer valley and the Hürtgen Forest.

Action of 6 July 1697: This series of battles took place in 1697 when the Venetian fleet, under Bartolomeo Contarini, hunted down the Turkish fleet in the Aegean Sea.

Battle of Rawicz: The Battles of Rawicz refer to the armed anti-German rebellion by ethnic Polish residents of the town of Rawicz (German: Rawitsch), located in Province of Posen of the German Empire.  The two battles took place in February 1919, during the Greater Poland Uprising, and resulted in Polish defeat.

Battle of Nanyang: The Battle of Nanyang took place in 1641 and 1642 in Nanyang, an important city in Henan Province.  This city is an ancient original place of the Silk Road.  At the end of Ming Dynasty, many battles took place in Nanyang.  In 1641, a person named Li Zicheng "(李自成)" attacked Nanyang and finally took control of the west of this city.  In 1642, he attacked Nanyang again and took control of the whole city.  And that war was called Battle of Nanyang, which lasted nearly a year.

War of Independence of Brazil: The War of Independence of Brazil (also known as the Brazilian War of Independence) was waged between the newly independent Empire of Brazil and United Kingdom of Portugal, Brazil and the Algarves which had just undergone the Liberal Revolution of 1820.  It lasted from February 1822, when the first skirmishes took place, to March 1824 with the surrender of the Portuguese garrison in Montevideo.  The war was fought on land and sea and involved both regular forces and civilian militia.  Land and naval battles took place in the territories of Bahia, Cisplatina and Rio de Janeiro provinces, the vice-kingdom of Grão-Pará, and in Maranhão and Pernambuco, which today are part of Ceará, Piauí and Rio Grande do Norte states.

Supporting paragraphs: Operation Clipper Battle of Hürtgen Forest
Answer: Battle of Hürtgen Forest