This chapter presents the hypothesis that working memory and language evolved in tandem. It reviews the evolutionary origins of each of the components of Baddeley’s working memory model and their role in the evolution of language. The chapter reviews the gradualist position that language did evolve slowly from aurally directed early primate calls and notes that the primary purpose of language has always been communication. The chapter also presents the novel idea that the pragmatics of speech (the purposes of speech) also evolved in tandem with the evolution of working memory. The chapter also reviews the saltationist idea that something happened to language more recent than 100,000 years ago, and that is the release of the fifth pragmatic of speech, the subjunctive mood, which expresses wishes and ideas contrary to fact. The subjunctive mood required fully modern working memory capacity, sufficient phonological storage capacity, and an enhanced visuospatial sketchpad, which are also critically involved in episodic memory recall and simulation. The phenotypic result of this genotype meant that thought experiments could be conducted in a recursive manner. We propose that the fruits of Homo sapiens’s cultural explosion, cave art, creative figurines, and highly ritualized burials, were the direct result of the wishes and imaginings that arise from subjunctive thinking and subjunctive language.