Question: When did Germany invade the continent where the river Tekezé River turns into is located in World War 2?

full_context: Document 1: Tekezé River: The Tekezé River rises in the central Ethiopian Highlands near Mount Qachen within Lasta, from where it flows west, north, then west again, forming the westernmost border of Ethiopia and Eritrea from the confluence of the Tomsa with the Tekezé at to the tripoint between the two countries and Sudan at . After entering northeastern Sudan at the tripoint it joins the Atbarah River, which is a tributary of the Nile. The Tekezé is perhaps the true upper course of the Atbarah, as the former follows the longer course prior to the confluence of the two rivers.
Document 2: Eritrea: Eritrea can be split into three ecoregions. To the east of the highlands are the hot, arid coastal plains stretching down to the southeast of the country. The cooler, more fertile highlands, reaching up to 3000m has a different habitat. Habitats here vary from the sub-tropical rainforest at Filfil Solomona to the precipitous cliffs and canyons of the southern highlands. The Afar Triangle or Danakil Depression of Eritrea is the probable location of a triple junction where three tectonic plates are pulling away from one another.The highest point of the country, Emba Soira, is located in the center of Eritrea, at 3,018 meters (9,902 ft) above sea level.
Document 3: Yangtze: The river originates from several tributaries in the eastern part of the Tibetan Plateau, two of which are commonly referred to as the ``source ''. Traditionally, the Chinese government has recognized the source as the Tuotuo tributary at the base of a glacier lying on the west of Geladandong Mountain in the Tanggula Mountains. This source is found at 33 ° 25 ′ 44'' N 91 ° 10 ′ 57 ''E ﻿ / ﻿ 33.42889 ° N 91.18250 ° E ﻿ / 33.42889; 91.18250 and while not the furthest source of the Yangtze, it is the highest source at 5,342 m (17,526 ft) above sea level. The true source of the Yangtze, hydrologically the longest river distance from the sea, is at Jari Hill at the head of the Dam Qu tributary, approximately 325 km (202 mi) southeast of Geladandong. This source was only discovered in the late 20th century and lies in wetlands at 32 ° 36 ′ 14'' N 94 ° 30 ′ 44 ''E ﻿ / ﻿ 32.60389 ° N 94.51222 ° E ﻿ / 32.60389; 94.51222 and 5,170 m (16,960 ft) above sea level just southeast of Chadan Township in Zadoi County, Yushu Prefecture, Qinghai. As the historical spiritual source of the Yangtze, the Geladandong source is still commonly referred to as the source of the Yangtze since the discovery of the Jari Hill source.
Document 4: Walaqa River: The Walaqa River, a tributary of the Blue Nile, is river in the Amhara Region of Ethiopia. Wegde is located to its north. Mida Woremo and Dera are to the south, while Kelala is to the northeast. The Walaqa River may have been the northern boundary of the historical province of Walaqa.
Document 5: North African campaign: Fighting in North Africa started with the Italian declaration of war on 10 June 1940. On 14 June, the British Army's 11th Hussars (assisted by elements of the 1st Royal Tank Regiment, 1st RTR) crossed the border from Egypt into Libya and captured the Italian Fort Capuzzo. This was followed by an Italian counter-offensive into Egypt and the capture of Sidi Barrani in September 1940 and again in December 1940 following a British Commonwealth counteroffensive, Operation Compass. During Operation Compass, the Italian 10th Army was destroyed and the German Afrika Korps -- commanded by Erwin Rommel, who later became known as ``The Desert Fox ''-- was dispatched to North Africa in February 1941 during Operation Sonnenblume to reinforce Italian forces in order to prevent a complete Axis defeat.
Document 6: Sobat River: The Sobat River is a river of the Greater Upper Nile region in northeastern South Sudan, Africa. It is the most southerly of the great eastern tributaries of the White Nile, before the confluence with the Blue Nile.
Document 7: First Battle of El Alamein: The First Battle of El Alamein (1 -- 27 July 1942) was a battle of the Western Desert Campaign of the Second World War, fought in Egypt between Axis forces (Germany and Italy) of the Panzer Army Africa (Panzerarmee Afrika, which included the Afrika Korps) (Field Marshal (Generalfeldmarschall) Erwin Rommel) and Allied (British Imperial and Commonwealth) forces (Britain, British India, Australia, South Africa and New Zealand) of the Eighth Army (General Claude Auchinleck).
Document 8: Flooding of the Nile: The flooding of the Nile is the result of the yearly monsoon between May and August causing enormous precipitations on the Ethiopian Highlands whose summits reach heights of up to 4550 m (14,928 ft). Most of this rainwater is taken by the Blue Nile and by the Atbarah River into the Nile, a less important amount is flowing through the Sobat and the White Nile into the Nile. During this short period, those rivers contribute up to ninety percent of the water of the Nile and most of the sedimentation carried by it, but after the rainy season, dwindle to minor rivers.
Document 9: North African campaign: The North African Campaign of the Second World War took place in North Africa from 10 June 1940 to 13 May 1943. It included campaigns fought in the Libyan and Egyptian deserts (Western Desert Campaign, also known as the Desert War) and in Morocco and Algeria (Operation Torch), as well as Tunisia (Tunisia Campaign).
Document 10: Nile: The Nile (Arabic: النيل‎, written as al-Nīl; pronounced as an-Nīl) is a major north-flowing river in northeastern Africa, and is the longest river in Africa and the disputed longest river in the world (Brazilian government claims that the Amazon River is longer than the Nile). The Nile, which is about 6,650 km (4,130 mi) long, is an "international" river as its drainage basin covers eleven countries, namely, Tanzania, Uganda, Rwanda, Burundi, the Democratic Republic of the Congo, Kenya, Ethiopia, Eritrea, South Sudan, Republic of the Sudan and Egypt. In particular, the Nile is the primary water source of Egypt and Sudan.The river Nile has two major tributaries, the White Nile and Blue Nile. The White Nile is considered to be the headwaters and primary stream of the Nile itself. The Blue Nile, however, is the source of most of the water and silt. The White Nile is longer and rises in the Great Lakes region of central Africa, with the most distant source still undetermined but located in either Rwanda or Burundi. It flows north through Tanzania, Lake Victoria, Uganda and South Sudan.  The Blue Nile begins at Lake Tana in Ethiopia and flows into Sudan from the southeast. The two rivers meet just north of the Sudanese capital of Khartoum.The northern section of the river flows north almost entirely through the Sudanese desert to Egypt, then ends in a large delta and flows into the Mediterranean Sea. Egyptian civilization and Sudanese kingdoms have depended on the river since ancient times. Most of the population and cities of Egypt lie along those parts of the Nile valley north of Aswan, and nearly all the cultural and historical sites of Ancient Egypt are found along river banks.
Document 11: Afrika Korps: The Afrika Korps or German Africa Corps (, DAK ) was the German expeditionary force in Africa during the North African Campaign of World War II. First sent as a holding force to shore up the Italian defense of their African colonies, the formation fought on in Africa, under various appellations, from March 1941 until its surrender in May 1943. The unit's best known commander was Field Marshal Erwin Rommel.
Document 12: Medjerda River: The Medjerda River (), the classical Bagrada, is a river in North Africa flowing from northeast Algeria through Tunisia before emptying into the Gulf of Tunis and Lake of Tunis. With a length of , it is the longest river of Tunisia. It is also known as the Wadi Majardah or Mejerha ().
Document 13: Balagas River: Balagas River is a river of northern Ethiopia. A tributary of the Tekezé, its own tributaries include the Balessa and Dorana rivers.
Document 14: Erwin Rommel: Field Marshal Erwin Rommel (c. 1942) Birth name Johannes Erwin Eugen Rommel Nickname (s) ``The Desert Fox ''(1891 - 11 - 15) 15 November 1891 Heidenheim, Württemberg, German Empire 14 October 1944 (1944 - 10 - 14) (aged 52) Herrlingen, Württemberg, Nazi Germany Buried Cemetery of Herrlingen Allegiance German Empire (1911 -- 1918) Weimar Republic (1919 -- 1933) Nazi Germany (1933 -- 1944) Service / branch Army of Württemberg Reichsheer German Army Years of service 1911 -- 1944 Rank Generalfeldmarschall Commands held 7th Panzer Division Afrika Korps Panzer Army Africa Army Group Africa Army Group B Battles / wars See battles World War I First Battle of the Argonne (1915) Masivul Lesului and Oituz Campaigns (1916 -- 1917) Battle of Caporetto (1917) World War II Invasion of Poland Fall of France Battle of Arras (1940) Siege of Lille (1940) North African Campaign Operation Sonnenblume (1941) Siege of Tobruk (1941) Operation Brevity (1941) Operation Battleaxe (1941) Operation Crusader (1941) Battle of Gazala (1942) Battle of Bir Hakeim (1942) First Battle of El Alamein (1942) Battle of Alam Halfa (1942) Second Battle of El Alamein (1942) Battle of El Agheila (1942) Battle of the Kasserine Pass (1943) Battle of Medenine (1943) Battle of Normandy (1944) Awards Iron Cross, First Class Pour le Mérite Knight's Cross of the Iron Cross with Oak Leaves, Swords and Diamonds Spouse (s) Lucia Maria Mollin (m. 1916) Relations Manfred Rommel (1928 -- 2013), son Gertrud Stemmer (1913 -- 2000), daughter Signature
Document 15: Atbarah River: The Atbarah River (; transliterated: Nahr 'Atbarah) in northeast Africa rises in northwest Ethiopia, approximately 50 km north of Lake Tana and 30 km west of Gondar. It flows about 805 km (500 mi) to the Nile in north-central Sudan, joining it at the city of Atbarah (). The river's tributary, the Tekezé (Setit) River, is perhaps the true upper course of the Atbarah, as the Tekezé follows the longer course prior to the confluence of the two rivers (at 14° 10' N, 36° E) in northeastern Sudan. The Atbarah is the last tributary of the Nile before it reaches the Mediterranean.
ground_truth: in February 1941
sub_queries: What river does Tekezé River turn into? Answer: Atbarah River
Atbarah River >> continent Answer: Africa
when did germany invade Africa in world war 2 Answer: in February 1941