During 1870, Britain and Russia continued colonial expansion and aggression on both sides of Afghanistan, and soon the border was connected with the soil of Afghanistan, posing a threat to Afghanistan. Therefore, in order to prevent the occupation of the motherland's territory, Afghanistan accepted a series of unequal treaties proposed by Russia and refused the visit of British envoys. For this reason, Britain launched a war against Afghanistan, known as the second Afghan war in history. Later, under the heroic resistance of the Afghan people, the British colonial army was beaten black and blue, and Britain was forced to stop its aggression against Afghanistan. The third war in Afghanistan broke out in 19 19, because capitalism in Afghanistan began to sprout, and the outbreak of World War I contained British military power; The beginning of the October Revolution inspired Afghan leaders. 19 19 In February, Afghan reformists came to power and declared independence. Britain didn't want to give up the colony of Afghanistan, so the third Afghan war broke out. 192 1 year, under various pressures, Britain was forced to sign a contract and declare its recognition of the independence of Afghanistan.