We know that many receive haskamos (rabbinic endorsements) before printing their sefer. However, this wasn’t always the case. The practice of obtaining haskamos was generally not welcomed initially due to their non-Jewish origin. As a result, a number of notable sefarim were published without any haskamos.
Haskamos gained popularity and became mainstream following the Shabbsai Tzvi fiasco in the 1600s and the subsequent messianic fervor. This was in order to safeguard against the inclusion of heretical ideas in books. By the 1700s, nearly every sefer had haskamos.
The Chassam Sofer (1762-1839) was a big proponent of a sefer having haskamos, as he writes in a teshuva. On the other hand, the Pele Yoatz (1785-1828) as well as R' Yonasan Eibshitz (1690-1764) opposed the idea of receiving haskamos for a sefer. The Pele Yoatz writes that he was displeased with this idea because it’s like the author saying “honor me” since the haskamos are in order to glorify and exalt the author...
