The Industrial Revolution contributed significantly to social class changes during the 19th century by transforming economies from agrarian to industrial. This transition led to the emergence of a new middle class, comprised mainly of factory owners, merchants, and professionals, who gained influence and wealth. Conversely, the working class faced harsh conditions in factories, leading to urban overcrowding and labor exploitation. This disparity spurred organized labor movements and calls for reform, advocating for workers' rights and better living conditions. The resulting tensions between classes set the stage for political changes and social reforms, influencing labor laws and economic structures.