How long Coriantum, son of Emer, reigned is not stated, but assuming he was king until he died, he reigned for nearly a hundred years. He lived forty years after his first wife died (v. 24), and probably somewhere near sixty years before his first wife died. Emer reigned at least sixty-two years (v. 16 above), and Com reigned at least forty-nine years (v. 25). Therefore, the Jaredites had three generations of righteousness and prosperity for over two hundred years. Did they establish a Zion society? It seems they did. One of the characteristics of the Nephite Zion society was the length of physical life being extended (see 4 Nephi 1:18–21, and comments in chapter 1 of this work). Other indications of a Zion society was Emer seeing the Son of Righteousness (Ether 9:22 above), and Coriantum walking in the steps of his father (v. 23).
Just as the Nephite Zion society began to decline after the second generation, (see 4 Nephi 1:22 ff), the Jaredite decline began during the third generation. Com reigned and his son Heth began to embrace the secret plans of old which led to Heth slaying his father (Ether 9:27). The Zion society was lost, or at least wickedness again prevailed.