Thomas Aquinas was a Scholastic theologian of the 13th century whose thought was a seminal syncretisation of ancient philosophy and medieval Christian doctrine as well as a bridge into modern thought. Born in 1225 to a wealthy Sicilian family, Thomas was set aside for theological training from an early age, studied philosophy and theology in Naples and Paris, and joined the Dominican monastic order in 1245. He taught in both France and Italy, serving for some time as papal theologian, and produced a huge corpus of writings, including his famous and unfinished Summa Theologiae, a systematic theology for the training of priests. This work especially became a core text in Catholic, and more broadly Western, thought. After his death in 1274, Thomas was first condemned by the bishop of Paris for the rationalism of his theology, but much later in 1567, he was declared a Doctor of the Church, and later still, canonised.