Integration of history of mathematics (HOM) in mathematics education is emerging as frontier endowed with utility to stem decline in uptake, enhance performance and alter the negative perceptions about the subject. This case study sought to explore the influence of history of mathematics on grade eleven girls' perceptions of the Theorem of Pythagoras in particular and mathematics in general. In this exploratory study, the genetic approach of HOM was used in teaching the Theorem of Pythagoras. Findings indicate that the inclusion of aspects of the history of mathematics catalysed positive learner perceptions of the Theorem and mathematics in general. Notable changes in learner perceptions included affirmations of an increased level of motivation and confessed improvement in readiness of grade eleven learners in tackling challenging tasks involving the Theorem of Pythagoras. Learners also alluded to increased confidence in dealing with proofs, enjoying making their own discoveries and solving mathematical problems in general.