Complex sentence: Howell came from Terre Haute and traveled 100 mile, until heapparently came to the land that became Pawnee after being run out of town, and wondering the plains, until he came to a spot that seemed "good enough".
Split into simpler sentences: Howell came from Terre Haute and traveled 100 miles until he apparently came to the land that became Pawnee after being run out of town. Wandering about the plains until he came to a spot that seemed "good enough".