With the two kings slain, Gideon & Israel are victorious. Obviously troubling is Gideon’s taking of booty ; problematic is his comment about the battle at Tabor.
There is little I can find that even explorers that comment, most just write it off as a non-sequitor, but we just did have a battle at Tabor with Barak and Deborah and that was against Canaanites and King Jabin. Midianites are not mentioned being on either side, so this comment takes a leap of reason to understand and so we must infer that the Midianites were part of the battle.
Next, when Gideon asks What were these men like? The kings says that they had the bearing like “him” as of kings. We do know that his father Joash was the head of his community and as such had Canaanite deities in his front yard which was the communal worship area.
If we take the two kings literally and say that they were not flattering their captor by complementing that he was like a king but actually reflecting on the resemblance, here we can only understand that Gideon’s father, Joash had married Canaanite royalty which is why Gideon’s half brothers, “sons of my mother” were full Canaanites which now means that these were enemies of Deborah and Barak and that the Midianites had once been friends of Israel and fought on the Israeli side at that battle when they killed two Canaanite Kings.
Allies change with times. In WWII we were allies with the Soviets, now we are not, so again using logic, we have to infer that the Midianites saw the power vacuum created by the fall of the Canaanite nation and decided to fill it against their former allies. We also have to infer that the title of kings is somewhat like bank vice-presidents; easily obtained for public or military standing.
All of this helps us in understanding what has happened and of course we wonder why the Lord chose Gideon, but Gideon’s actions rather explain that as well: sometimes the Lord has to make do with the best of the lot because there really is no one else around and while you think that your neighbor would be a better choice than you, you really do not know what dwells in his heart, but the Lord does and if you are the only one to hear the “call” you have to trust in that alone and accept it for what it is – divine Providence or as Jesus put it so eloquently in the Lord’s Prayer…”Thy will be done in earth, As it is in heaven.”