When was communism conceived?

'Communism' is a nickname for a political ideology that was developed over a long period of time. There is no point in trying to find one single 'year of creation'. It is very closely associated with the philosophy of Karl Marx (1818-1883). From about 1870 onwards most socialist parties in Europe were in one sense or another Marxist. The largest group of Russian Social Democrats, the Bolsheviks headed by Lenin, made very considerable changes to Marxism.