This happened because of all the sins which Baasha and his son Elah committed and which they made Israel commit. They angered the Lord God of Israel with their worthless idols. ¹ 

In the thirty-sixth year of Asa’s reign, King Baasha of Israel attacked Judah, and he established Ramah as a military outpost to prevent anyone from leaving or entering the land of King Asa of Judah. ¹ 

“I want to make a treaty with you, like the one our fathers made. ¹  See, I have sent you silver and gold. Break your treaty with King Baasha of Israel, so he will retreat from my land.” ² 

King Asa ordered all the men of Judah to carry away the stones and wood that Baasha had used to build Ramah. ¹  He used the materials to build up ²  Geba and Mizpah.

Now the cistern where Ishmael threw all the dead bodies of those he had killed was a large one ¹  that King Asa had constructed as part of his defenses against King Baasha of Israel. ²  Ishmael son of Nethaniah filled it with dead bodies. ³