By spring 1941, following Himmler's orders, ten concentration camps had been constructed in which inmates were subjected to forced labour.

By the end of 1941, the Soviet military had suffered 4. 3 million casualties and German forces had advanced 1, 050 miles ( 1, 690 kilometers ).

By December 1941, Hitler's troops had advanced to within 20 miles of the Kremlin in Moscow.

By the end of 1943, the Soviets occupied half of the territory taken by the Germans from 1941 – 1942.

By 1941, Germany had given up hope of evicting the Allies from the island and the constant air raids stopped.

By 1857 he had accumulated over 800 pages of notes and short essays on capital, landed property, wage labour, the state, and foreign trade and the world market ; this work did not appear in print until 1941, under the title Grundrisse.

By September 1941, Philby was working for Section V of MI6, responsible for offensive counter-intelligence.

By early 1941, Fuchs had returned temporarily to Edinburgh.

By the winter of 1941 – 1942 just 39 percent of the fighter force was operational and possessed just 60 more combat aircraft than it did in June 1941 despite its increased commitments.

By early 1941, portable centimetric airborne radars were being tested in American and British aircraft.

By the third week in February 1941, 680, 000 German troops were stationed on the Romanian-Soviet border.

By 1941, the official newspaper, El País, had adopted an overtly pro-German stance.

By 22 June 1941 there were only 1, 475 T-34s and KV series tanks available to the Red Army, and these were too dispersed along the front to provide enough mass for even local success.

By 1941, President Roosevelt and Prime Minister King made an executive agreement to build the joint hydro and navigation works, but this too failed to receive the assent of Congress.

By 1918 it became part of the newly formed Kingdom of Serbs, Croats, and Slovenes, and remained so until 1941, apart from a brief period of six months in 1920 when Skopje was controlled by the Yugoslav Communist Party.

By the end of 1941, Roosevelt had appointed seven justices and elevated Harlan Fiske Stone to Chief Justice.

By late 1941, the Army Research Center at Peenemünde possessed the technologies essential to the success of the A-4.

By November 1941, it was becoming known in the upper reaches of the Nazi leadership and government offices that Hitler intended all the Jews of Europe to be deported to the eastern territories and executed by whatever means.

* Robert A. Heinlein's By His Bootstraps ( 1941 ) features a plot in which a man interacts with different older versions of himself that travel by way of a " Time Gate ", with all the interactions revisited later in the story from the perspective of the now-older man, everything being tied together in a completely self-consistent way.

By the end of 1941, Germany occupied a large part of Europe and its military forces were fighting the Soviet Union, nearly capturing Moscow.

By 1941 the Italians had suffered defeats in Greece and against the British in Egypt.

By 1941 he was earning a good wage, enough to pay for music lessons with Alberto Ginastera, an eminent Argentine composer of classical music.

By 1941, the SD had been organized into the following sections:

** By road to Ngaoundéré, in Cameroon, and then by rail to Douala

** By road to Maiduguri, in Nigeria, and then by rail to Port Harcourt

By linking with the existing railway network of the Eastern United States, the road thus connected the Atlantic and Pacific coasts of the United States by rail for the first time.

By rail: The Madrid-Irun in Vitoria is one of their most important stops.

By 1852, regular rail transportation from Columbia to Baltimore, Philadelphia, Pittsburgh, and Harrisburg made the town the commercial center for the area halfway between the county seats of Lancaster and York.

By this time Wright ’ s Ferry had ceased its operations, having been supplanted by rail and bridge traffic.

By 1896 the rail line had been extended to Biscayne Bay.

By rail, the regional trains and buses of the TER Pays de la Loire link major towns and cities of the Pays de la Loire and adjoining regions, including those of the département.

By the end of the 19th century, three rail lines served Pontiac and the city attracted carriage and wagon factories.

By 1906, 650 carloads of oranges and 250 carloads of lemons were shipped annually by rail.

By the late 19th century, however, rail connections to New York, Hartford, Pittsburgh and Boston gave visitors ready access to Norfolk's cool summers and clean air, and Norfolk soon evolved into a fashionable resort as its small industry declined.

By 1881 two rail lines and a road which intersected the area were added.

By the 1900s Brooks began to grow due to the rail road.

By 1854, rail service was established to Deer Grove and in 1859 the line was incorporated into the Chicago and Northwestern Railway system.

By 1945 the rail system of served the heart of the agricultural district of Illinois and many great industrial centers.

By May of the following year regular rail service was established.

By the early 1900s, Madisonville was a rail hub, coal mining center, and had a large tobacco market.

By 1881, a line was completed across Sinepuxent Bay to the shore, bringing rail passengers directly into the town.

By 1900, a third, all electric powered passenger rail line known as the Detroit United Railway ( D. U. R.

By 1890, Pipestone had train service on four different rail lines and had become a travel and business center hub for southwestern Minnesota.

By the turn of the century the city Neosho was a thriving community connected by three rail lines and exporting a variety of products and agricultural produce.

By 1907, the Chicago, Burlington & Quincy Railroad had taken over rail operations, and the town had a post office to serve the growing number of area homesteaders.

By the end of the year, the rail line had been extended as far as Toboggan Canyon, and construction was started on a pavilion at the summit to provide accommodations for the anticipated tourists.

By the early 1970s the southern rail line was completely abandoned and had been largely dismantled ; the northern line still functions to this day.