On November 20, 1917, the first successful tank use in battle occurred at the Battle of Cambrai in World War I as Britain uses the new technology to break through German lines. From the article:
"Battle of Cambrai
The World War I Battle of Cambrai marked the first large-scale use of tanks for a military offensive. Led by General Julian Byng, a British force of nine infantry divisions, five cavalry divisions and three tanks brigades sprung a surprise attack near Cambrai, France, on November 20, 1917. Although the British tanks and infantry overwhelmed German defenses on the first day, the cavalry exploitation was slow to develop. On Nov. 30, the Germans counterattacked and regained most of the ground lost. Officially finished by Dec. 7, the battle decisively demonstrated the power of tanks and altered the course of future warfare.
Cambrai was famous for two things: it saw the first great tank attack in history and, of equal importance, the first preregistration of artillery for an offensive. The idea for the large-scale use of British tanks started in early August 1917, when J. F. C. Fuller (second general staff officer, Tank Corps) (q.v.) and H. J. Elles (general staff officer, Tank Corps) put in a tank raid scheme for the Cambrai sector to General Headquarters. Eventually, headquarters agreed, and nine infantry divisions, five cavalry divisions, and three brigades of tanks were made available for the offensive under Julian Byng, general officer commanding, Third Army.
The key to the success of the Cambrai attack of November 20, 1917, was threefold. First, some 376 Mark IV fighting tanks were committed to the assault, to crush lanes through the wire and to protect the infantry as they advanced. Second, the artillery was able to do counterbattery and suppression work, and fire a barrage, without previous registration. This worked because the guns’ targets had been plotted on maps beforehand, while each gun had previously been fired behind the lines to establish its accuracy. Third, because of the first two factors, the Cambrai offensive would be a complete surprise.
At 6:20 a.m. on November 20, tanks and infantry advanced with great success against an astonished German defense. By nightfall, gains of two to three miles had been achieved. However, cavalry exploitation was slow to develop, and although more gains were made in the next nine days, German reserves halted the attack. Then, on November 30, a German blitzkrieg counterattack recaptured much of the ground lost. The surprise storm troop tactics used here anticipated the methods of the German 1918 spring offensives (see Ludendorff, Erich and Ludendorff Offensive). However, the original tank and artillery combined attack at Cambrai had forever altered the modern battlefield."