Book 1 is dominated by psalms of David and consists mostly of personal psalms that arose out of his own experiences. Book 2 was probably compiled by Solomon and exhibits more of a national interest. Book 3 was probably compiled soon after the destruction of Jerusalem in 586 B.C., since Psalms 74, 79, and 89 all have references to this event. David may have compiled Book 4, which focuses more on corporate worship than Book 1 does. Book 5 is also liturgical, but contains several postexilic (after the exile in 586 B.C.) psalms. It probably came into being after the return of 537 B.C. Then a scribe, perhaps Ezra (444 B.C.), probably wrote Psalms 146‑50 as a conclusion and Psalm 1 as an introduction and compiled the five books into one.