Why was the cleveland massacre significant in the formation of standard oil?

the Cleveland Massacre was significant in the formation of Standard Oil because through it, Standard Oil absorbed 22 of its 26 competitors.

This was because Rockefeller (founder of Standard Oil) planned the cleveland massacre to corner the US oil market. During the early 1870s, near the oil regions of Pennsylvania, several oil refining companies competed with each other. Huge competition for black oil has made prices volatile. Some companies were willing to give nonprofits just to gain an advantage over the competition. Rockefeller, having a Messianic thought of himself, saw the competition as a waste. His idea was that, in order for all oil potential to be achieved, the competition should be stopped. And so, he saw Standard Oil as the way to unite the entire oil refining industry.  Thus, Rockefeller used the South Improvement Company to obtain large leverage in the production of smaller oil refineries to join or be purchased by Standard oil.

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