Chapter 108

David.

MSB note says David here combines two of his previous psalms - 57 and 60 - leaving out the laments.  That makes this almost entirely a commemoration of God's victories. 

1st Stanza, I will sing of your steadfast love.

2nd, Answer my prayers

3rd, God has promised the people Canaan.  Israel is God's.

4th, Asking God to go before them into battle.  David says this:

11 Have you not rejected us, O God? You do not go out, O God, with our armies. [Psa 108:11 ESV]

This followed with a prayer that God would help them against the foe.  There's no way to tell for sure what specific event this may be about.  David was constantly beset by enemies after his sin with Bathsheba, and this could have been just about any one of those - and I am sure there are many not recorded.  To me, the important thing is that here again God had "left Israel alone".  Removing His protection is what He often does when we turn away from Him.  It is not that He always pro-actively sends problems, plagues, pestilence and war so much as He stops protecting nations from the natural greed, violence, and deceit that characterizes fallen man. 

2021 - Those first 4 verses are another example of what a music lover David was.  He wants instruments playing, and he wants to sing songs.  Put the two together and you have the songs and music we use in worship today.  I really do think David is the one who introduced musical accompaniment to worship songs - to Psalms.  Perhaps that's why he wrote so many.  He was an accomplished song writer.