Manufacturing industry was most common in the western states in the 1800s.
<u>Explanation:</u>
The occurrence of the American Revolution in the last few decades of the 1700s resulted in worsening of ties between the western states and Great Britain.
This badly affected the supply of goods that came from various European countries.
The people in the western states started facing scarcity of essential goods and thus, they moved on to manufacture the necessary goods by themselves.
Increase in the manufacturing activities also gave the regional economy a good stability.
The railroad mileage increase was the highest in the western states by 1860s and for decades after that.
That proved enough for the manufacturing industry to flourish more in the latter half of the 1800s.