Jacob 1:11 - 1:15
Jacob 1:11 Wherefore, the people were desirous to retain in remembrance his name. And whoso should reign in his stead were called by the people, second Nephi, third Nephi, and so forth, according to the reigns of the kings; and thus they were called by the people, let them be of whatever name they would.
Because of the goodness of Nephi and their love for him, they now name their future kings after him. It did not matter what the person’s actual name was he was crowned Nephi II and so on.
Jacob 1:12 And it came to pass that Nephi died.
Nephi dies and Jacob now becomes the spiritual leader of the Nephites. (It would interesting to know if other people, who were already living in the promised land when Lehi landed there that had joined up with the Nephites. If they were just the actual descendents of Lehi, their numbers would not be that great even after 50 years of so. But I suspect that there were others particularly those who Nephi and his follower may have preached to that joined up them.)
Jacob 1:13 Now the people which were not Lamanites were Nephites; nevertheless, they were called Nephites, Jacobites, Josephites, Zoramites, Lamanites, Lemuelites, and Ishmaelites.
It is interesting that the Nephites, even thought they referred to themselves as Nephites, they also know from which of the sons of Lehi they were descendents of as did the Lamanites.
Jacob 1:14 But I, Jacob, shall not hereafter distinguish them by these names, but I shall call them Lamanites that seek to destroy the people of Nephi, and those who are friendly to Nephi I shall call Nephites, or the people of Nephi, according to the reigns of the kings.
However, Jacob will not refer to his people by all their clan names but only as Nephites. All those who are trying to destroy the Nephites will be called Lamanites to make it easier on the writers and readers of this record.
Jacob 1:15 And now it came to pass that the people of Nephi, under the reign of the second king, began to grow hard in their hearts, and indulge themselves somewhat in wicked practices, such as like unto David of old desiring many wives and concubines, and also Solomon, his son.
As it seems almost natural for people, the Nephites begin to become less and less faithful to the gospel in spite of all the preaching of Jacob and the other church leaders. They were now engaging in wickedness such as more than one wife like unto some men of old such as David and Solomon.