Cândido Mariano da Silva Rondon, or Marechal Rondon (5 May 1865 – 19 January 1958) was a Brazillian officer born in Matto Gross are in Brazil. He was bi-racial in being Portuguese descent and native American. He was a Brazilian patriotic in which he favored development for his people and the country. He championed the cause for the rights and welfare of the indigenous people. He was the man whom Theodore Roosevelt would need for the journey to the unknown river which is called the ‘river of doubt’.

When Theodore Roosevelt undertakes the trip to South America, he was then recommended by the Brazilian government to navigate the River of doubt now known today as the Roosevelt river. He had appreciation and admiration for Roosevelt and remained friends.