Blake was very interested in the social conditions of his day and had radical ideas about the welfare and education of children. He would undoubtedly have witnessed at first hand the usually deplorable conditions in which child chimney sweeps were forced to work. Because of coal fires London was an extremely smoky city even up till comparatively modern times and the narrow chimney openings needed someone small to climb into them to clean out the soot that otherwise would have blocked the flu or caught fire. Therefore very small and young boys were used for the task and their lives were frequently at risk. Even if they survived falls and other hazards such as getting trapped, the constant inhaling of soot and fumes would have been very damaging to their respiratory systems. Blake's empathy for them surely inspired poems like this.
William blake was an english poet who was guided by emotion and imagination.His lyrics were short,very simple expressed and often packed with meanings and thoughts.At the first sight he had seen millions of children calling sweep,sweep,sweep in the street by seeing this william blake had a strong impact in his mind.He had seen children after the chimney were cleaned, the children were covered in soot .He had also seen that they have no time to play and run.For awaring to other people how the children are being treated he decided to write a poem based on the lifestyle of a chimney sweeper.