The practice of vertical integration contributed most to Andrew Carnegie's ability to form a monopoly. Vertical integration is a process of combining different stages of production such as manufacturing, supplying, distributing, retailing, etc, under the umbrella of one company.
The American Civil War was not inevitable and it could have been easily avoided. But, once it crossed a certain point, there was no turning back. The Civil War was fought in the years 1861-1865 over the issue of slavery.
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