Is this the face of the Slavic pagan Goddess Mokosh? If so, it would be one of the only remaining images of the powerful fertility deity whose influence eroded with the arrival of Christianity among the Kievan or Kyivan Rus in the 10th century.
Much about this period is unknown, but the Kievan/Kyivan Rus was a powerful state in eastern and northern Europe between the late 800s-mid-1200s. Blending Norse and Slavic heritage, it became famed because of its extensive use of northern trade routes and strong military. Unsurprisingly, the modern countries Ukraine, Russia, and Belarus each claim its legacy.
The Kiev/Kyivan Rus power-minded ruler Vladimir the Great (c. 958-1015) converted his state to Christianity. The Medieval source the _Primary Chronicle_ says that he first looked around and rejected Islam because it prohibited alcohol, and Judaism because the God of the Jews allowed his chosen people to be deprived of their homeland. Really Vladimir was probably bewitched by the beauty and glory of the Byzantine Empire and the wealth of the Orthodox Christian Churches there.
However, before converting, Vladimir had practiced the paganism of his Kievan/Kyivan ancestors, building a temple on a hill in Kyiv/Kiev dedicated to six Gods, with Mokosh as the only female divinity in the group. Mokosh was a Goddess of fertility and protector of women (her name might derive from the word “moisture” and she might have her roots in the Finnic peoples of the Vogul).
The sculpture featured here, now in Poland, shows one side of an 8.8-foot high stone pillar from the 9th century. Many scholars think it depicts four faces of the same God named Swiatowid. However, historian Boris Rybakov argues that it shows four different deities, two male, and two female, stating that the one featured here with the horn of plenty represents Mokosh.