Kommentar zu Divrej Hajamim II 18:2

And he went down at the end of years And in I Kings (22:2) it is written: “And it was in the third year, that Jehoshaphat came down, etc.” This refers to the third year since he had released Ben Hadad (ibid. 20:34).

and he enticed him to go up to Ramoth Gilead as is written in the Book of I Kings (22: 3): “Do you know that Ramoth Gilead is ours,” because when Jacob built the mound [of stones] there and called it Galead, he took possession of it, and our forefathers took Gilead and the heights (רָמוֹת), which are a continuation and an attachment to the city. But when our forefathers in Moses’ time seized Gilead, they were silent and refrained from taking it, because they did not care for it, or perhaps in Moses’ time, they did take it, but later the nations took it from Israel’s hands, but it is [in fact] ours.