This preliminary study examines long waves of strikes in South Africa over the period 1900-2015. In particular, it analyses the defensive and offensive character of strikes located within the Marxian theory of long waves of capitalist development. This analysis confirms a general tendency for offensive and defensive strikes to be linked to the upturns and downturns of the capitalist business cycles and long waves of capitalist development (what can be termed the objective factor). However, while giving primacy to the objective factor, Marxian analysis has consistently maintained the relatively long-term autonomy of the class struggle (what can be termed the subjective factor). It is in view of the latter that I employ the Marxist theory of long waves of capitalist development through which the dialectic of the objective and the subjective factors of historical development of strikes can be examined.