Final answer:
Hammurabi, the ruler of the Babylonian Empire, is credited as the precursor of the professional scribal class due to his creation of the Code of Hammurabi, which was inscribed on stone steles throughout his empire.
Step-by-step explanation:
Hammurabi is believed to be the precursor of the professional scribal class. As the ruler of Babylon during the first half of the eighteenth century BCE, Hammurabi was responsible for the unification of Mesopotamia under his rule and the establishment of a lasting legacy through the creation of the Code of Hammurabi. This code was one of the earliest and most complete written legal codes and is a significant early example of the idea of establishing consistent laws that were written down and accessible to the people. The Code of Hammurabi was inscribed on stone steles that were erected throughout his empire, which not only informed the subjects of the law but also required a professional scribal class to create and maintain these records.