Step 1: Understanding the Concept:
Keertan is a traditional form of storytelling combined with music and singing, used primarily for religious and social awakening in Maharashtra.
Step 2: Detailed Explanation:
Saint Namdev (Sant Namdeo) is traditionally regarded as the first Keertankar of Maharashtra. He played a pivotal role in the Varkari sect and traveled widely, even to Punjab, spreading the message of devotion and equality through his Keertans. He is credited with establishing the structure of the "Naradiya" style of Keertan.
Step 3: Final Answer:
The first Keertankar is Saint Namdev.