Land was determined by lot for the tribe of Manasseh, who was actually Joseph's oldest son. Gilead and Bashan belonged to Machir, who was Manasseh's oldest son and Gilead's father. This was because he was a warrior.
References for Joshua 17:1
So an allotment took place for the rest of the clans of the people of Manasseh—for the people of Abiezer, Helek, Asriel, Shechem, Hepher, and Shemida. These were the sons of Manasseh the son of Joseph, the male descendants by their clans.
Zelophehad was Hepher's son, Gilead's grandson, Machir's great-grandson and Manasseh's great-great-grandson. Zelophehad had no sons, only daughters, who were named Mahlah, Noah, Hoglah, Milcah, and Tirzah.
The daughters approached Eleazar the priest, Joshua, Nun's son, and the leaders. They said, "The LORD commanded Moses to give us a legacy along with our male relatives." So in agreement with the LORD's command, they were given a legacy along with their uncles.
Manasseh had ten parcels in addition to the land of Gilead and Bashan on the other side of the Jordan.
This was because the daughters of Manasseh received a legacy along with his sons. The land of Gilead belonged to the rest of the people of Manasseh.
The border of Manasseh ran from Asher to Michmethath, which is opposite Shechem. The border went south to the population of En-tappuah.
The land of Tappuah belonged to Manasseh. But Tappuah itself belonged to the people of Ephraim, even though it was on the border of Manasseh.
The border went down by the Kanah Valley. South of the ravine are those cities that belong to Ephraim, even though they are located among the cities of Manasseh. The border of Manasseh lay on the north side of the ravine and ended at the sea.
What lay south of the border belonged to Ephraim, and what lay north of it belonged to Manasseh. The sea was its border. The territory bordered Asher on the north and Issachar on the east.
Belonging to Manasseh in Issachar and in Asher were Beth-shean and its dependent cities, Ibleam and its dependent cities, the population of Dor and its dependent cities, the population of En-dor and its dependent cities, the population of Taanach and its dependent cities, and the population of Megiddo and its dependent cities. (The third one is Naphath.)
References for Joshua 17:11
The people of Manasseh couldn't take over these cities, and the Canaanites were determined to live in this land.
When the Israelites grew strong, they subjected the Canaanites to hard labor but didn't remove them.
The tribe of Joseph spoke to Joshua: "Why have you only given us a single lot and a solitary parcel for a legacy? We are a numerous people whom the LORD has blessed so richly."
References for Joshua 17:14
Then Joshua said, "Yes, you are a numerous people. So go up to the forest and clear ground for yourselves there in the land of the Perizzites and Rephaim, because the Ephraimite highland is too small for you."
The people of Joseph said, "The highland isn't enough for us. But all the Canaanites who live in the valley region have iron chariots, both those in Beth-shean and its dependent cities and those in the Jezreel Valley."
Joshua then said to the house of Joseph, to Ephraim and to Manasseh, "You are a numerous people and possess great strength. You will have more than a single lot.
The highland will belong to you. Because it is a forest, you can clear it. Its farthest limits will be yours. You will definitely remove the Canaanites, even though they have iron chariots and are strong."