Urdaneta was born in Bogotá on 27 June 1890, during the administration of President Carlos Holguín Mallarino, his future father in law.

[3] At an early age Urdaneta showed great interest for politics and he enlisted in the Colombian Conservative Party.

On October 31, Congress is notified of the intentions of president Laureano Gómez to request leave of absence due to his illness.

Congress was persuaded by his impassionate appeal (the last wishes of a dying man), and elected Urdaneta as interim president.

Before he did so, Gómez requested Urdaneta to remove General Gustavo Rojas Pinilla from his post as Chief of Staff of the Army.

Within hours, that same afternoon, General Gustavo Rojas Pinilla, accompanied by other Generals of the Army's high command, presented himself before Urdaneta and stated: "In the name of the Army's high command, I have the charge to express to your Excellency that we are here to request that you continue acting as President of Colombia".

Urdaneta replied once again: "I am most grateful and moved by the Army's high command demonstration of trust and loyalty, but since this morning I am no longer the President, because Gómez has retaken his office.

In light of Urdaneta's reluctance to accept the Army's request, General Rojas Pinilla proclaimed himself to be in charge of the office of the presidency.