Joshua 22:9-12 - Eastern Tribes Build An Altar
9 And the children of Reuben, and the children of Gad, and the half-tribe of Manasseh returned, and departed from the children of Israel out of Shiloh, which is in the land of Canaan, to go to the country of Gilead, to the land of their possession, of which they were possessed, according to the word of the LORD by the hand of Moses. 10 And when they came to the borders of Jordan, that are in the land of Canaan, the children of Reuben, and the children of Gad, and the half-tribe of Manasseh built there an altar by Jordan, a great altar to the sight.
11 And the children of Israel heard it said, Behold, the children of Reuben, and the children of Gad, and the half-tribe of Manasseh, have built an altar over against the land of Canaan, in the borders of Jordan, at the passage of the children of Israel. 12 And when the children of Israel heard of it, the whole congregation of the children of Israel assembled at Shiloh, to go up to war against them.