Moses included the record of his appointment of Bezer, Ramoth, and Golan as the three cities of refuge east of the Jordan. He probably did so because this important event took place after his first address and before he delivered his second speech. The two and one-half tribes were beginning to settle in Transjordan.
The inclusion of this historical incident also serves a literary function. It provides a kind of intermission for the reader following the emotional climax at the end of the first address. It allows him or her to recover from its strong impact before the next long address begins.
Deuteronomy, as Leviticus, is essentially a narrative document. Moses interspersed much legal material in the narrative of Leviticus, and he interspersed much sermonic material in the narrative of Deuteronomy. In both books there is less narrative material than legal or sermonic material.