The notion of the labour-aristocracy is one of the oldest Marxian explanations of working-class conservatism and reformism. Despite its continued appeal to scholars and activists on the Left, there is no single, coherent theory of the labour-aristocracy. While all versions argue working-class conservatism and reformism reflects the politics of a privileged layer of workers who share in ‘monopoly’ super-profits, they differ on the sources of those super-profits: national dominance of the world-market in the nineteenth century (Marx and Engels), imperialist investments in the ‘colonial world’/global South (Lenin and Zinoviev), or corporate monopoly in the twentieth century (Elbaum and Seltzer). The existence of a privileged layer of workers who share monopoly super-profits with the capitalist class cannot be empirically verified. This essay presents evidence that British capital’s dominance of key-branches of global capitalist production in the Victorian period, imperialist investment and corporate market-power can not explain wage-differentials among workers globally or nationally, and that relatively well-paid workers have and continue to play a leading rôle in radical and revolutionary working-class organisations and struggles. An alternative explanation of working-class radicalism, reformism, and conservatism will be the subject of a subsequent essay.