Fate, doom, and free will have always proved to be controversial terms among philosophers. The chief problem is whether a deterministic power prescribes the destiny of creatures or they possess pure free will in shaping their destinies. Mulla Sadra, a 17th century Iranian philosopher, believes in a blending of determinism and free will which he develops in the terms of Qaza and Qadar respectively. He introduces a model of fate through which determinism and free will equally participate. Using the human soul as a model, Mulla Sadra points out that people meet their fate through several factors, one of which is free will. However, he concludes that free will and deterministic factors altogether stand within the circle of an omnipotent being. This paper presents a comparative study of J.R.R. Tolkien's The Silmarillion and Abul-Qasem Firdausi's Shahnameh. Both Indo-European mythologies are engaged with the clash of determinism and free will in the fabric of their plots. The authors of this paper argue that each mythology demonstrates a distinct system of free will/determinism dichotomy based on the yardstick of Mulla Sadra's theorem. To achieve this goal, the representative characters in both works are analyzed in the context of factors and actions the characters are involved with. The determinative factors, which define actions as free or deterministic, help bring a comparison between the systems of fate in the two works.