Old English strewian, streowian "to scatter," from Proto-Germanic *strawjan- (source also of Old Frisian strewa, Old Saxon strowian, Old Norse stra, Danish strø, Swedish strö, Middle Dutch strowen, Dutch strooien, Old High German strouwen, German streuen, Gothic straujan "to sprinkle, strew"), from suffixed form of PIE root *stere- "to spread." Related: Strewed; strewn; strewing.
<a href="https://www.etymonline.com/word/strewn">Etymology of strewn by etymonline</a>
Harper, D. (n.d.). Etymology of strewn. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/strewn