What were the achievements of bolivar, san martin, and dom pedro

Bolivar has helped a number of modern South American states become independent from the Spanish rule. Eventually, he became the Venezuelan President. 

San Martin was a general, who participated in the Spanish-American war of independence, and was the first president of Peru (under the name of "Protector of Peru). 

Dom Pedro was a Portuguese King (which at the time included Brazil as well) , who declared independence of Brazil, and reigned over Brazil only after that.